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TRRS Pinouts for Desire-like proper headphones without issues of direct plugging in

Sup all would anyone have the actual TRRS pinouts for the audio jack for the desire I would like to make a up a lead that will allow me to plug an ordinary pair of headphones in using a proper TRRS jack instead of a TRS jack. thanks. There are definately issues plugging in a headphone directly or maybe it is my unit faulty?
Edited, this topic will show you the best way to connect your headphones to your desire as some people will experiance problems with pluggin in normal 3.5 jack plug headphones, this is due to the desire using a trrs socket for the microphone instead of a trs socket that normal headphones use.

pretty sure it is:
tip - left audio
ring 1 (closest to tip) - right audio
ring 2 - data of some kind
shield - ground
Hope this helps

cheers for that, im having some peeps tell me that i can just plug in an ordinary pair of headphones into the phone without any ill effects, i am concerned that i will have a problem because headphones are trs jacks and the desire has the trrs 3.5 jack. can anyone confirm any details on this for me please

nah you can use a normal TRS 3.5mm jack with no problems. I guess that when you use a normal TRS jack then shield and ring 2 on the connector are both connected to shield on the jack so it adjusts the software accordingly. But yea, no problems.

cheers for that
edited, we have since discovered that this is not the case, please read the entire topic for the correct way to connect headphones to the desire.

standard 3,5 mm (TRS) headphones DO CAUSE ISSUES
Was about to resend my HTC Desire, because it randomly called, skipped music stopped the music, FM-radio freeze etc. from the moment I connected my high-end 3,5mm headphone (TRS type: 3 contacts).
No issues with the standard headset delivered with the HTC Desire (TRRS type: 3,5mm 4 contacts).
So, you might need a TRS -> TRRS adapter.
Anyone with other experiences???

Basically what I have found is that many of the normal headphones are not working correctly because it is a trrs socket that is used. To me this would mean that normal headphones shouldnt be used, I have tried various headphones but there are definately issues with them,
The main issue I was having was as you have said above and also the base wasnt right with them
I have since bought this
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130384433476&ssPageName=STRK:MEWNX:IT
which arrive today and when I am using this in conjunction with my headphones I now have the proper base to the set and NONE of the problems I was having when i was plugging them into the phone directly......... they just didnt sound right, now using griffin smarttalk this i can definately tell the difference now especially in the base, also this unit will lower the volume and allow you to make a call automatically with built in mike, clicking it twice doesnt skip the track suggested instead it will ring the last number dialled in the phone so a bonus actually to me
the straight adapters ie trrs to trs are very nearly the same price as this if not more expensive so i would recommend this all day long to you. At £9.75 delivered bargain m8, bought late evening on the 20th arrived this morning what more can i say, but if you are having issues it is definately in my eyes because of the difference in the trrs socket to the trs socket,
the base is fantastic on this phone now, before it was terrible, now i just need an equaliser to remove some of it

When you speak of "normal headphones", are you referring to simple 3.5 TRS headphones, or headphones with a mic ?
Cause if the majority of the headphones (without mic I mean) won't properly work with the Desire, it's a major flaw according to me.

I confirm: TRS (3 contacts, without mic) do not work...
...I tried 4 different 3,5mm stereo headsets (TRS type, 3 pole, without mic). NONE of them worked correctly (phenomenons as described above).
When you plug a 3 pole TRS headphone in the Desire 4 pole TRRS headphone output, a short circuit is generated between the first 2 internal contacts (seen from connector input: ground + control line).
I suspect that the Desire firmware cannot detect/handle this situation, and so it causes random actions (prev, next, call numbers, stop, play, ....)
I suspect that this issue could be solved with a firmware upgrade....

there is no way they would release hardware with a 3.5mm socket that you cant plug a 3.5mm jack into right? the firmware does detect when you use a TRS instead of a TRRS. You get a different icon on your notification bar for each of them. As ive said before my AKG's have worked perfectly so far and have shown none of the problems listed above.

This afternoon I quickly tested my Seinheiser PX100 headphones with a friend's desire and the Htc music player.
It worked flawlessly. Volume was good and it didn't play/pause/skipped tracks.
As I said it was a really quick test so I can't say for sure that everything's was okay.
Nonetheless apparently a lot of people experienced problems with numerous headphones. To me it's really a shame you can't even plug ANY 3.5mm jack headphones with the desire ...
I hope a software update could fix this.

I also had this problem when connecting my Desire to my car radio using an standard 3.5mm AUX cable. Will this cable solve my problem or will my car radio not be able to recognize a 4 pole cable?
http://cgi.ebay.nl/3-5mm-Male-TRRS-...erAccess_RL&hash=item5d28c530c1#ht_1252wt_939

I think this might be an issue of certain cables not making a full connection due to the shape of the case surrounding the socket. I had no problems with my headphones, sound was good and loud enough although I could see how it might not be loud enough for some.
I did start having issues when I plugged the aux lead in my car into the phone. The lead has a large shroud that obstructed the plug from being plugged all the way in. This gave the same problems as described in other posts, skipping tracks and also crashing the music software at one point.
I replaced the lead with another that had a better fit and the problems went away but I did notice when I leaned against the lead while it was playing music in my car it started skipping track again.
I wonder what HTC have to say about this....

DHel01 said:
I also had this problem when connecting my Desire to my car radio using an standard 3.5mm AUX cable. Will this cable solve my problem or will my car radio not be able to recognize a 4 pole cable?
http://cgi.ebay.nl/3-5mm-Male-TRRS-...erAccess_RL&hash=item5d28c530c1#ht_1252wt_939
Click to expand...
Click to collapse
I solved those problems with this lead- i dont think the one your showing will work for you
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220593400305
they come from china etc however only 5 days to arrive from ordering.
and I now enjoy trouble free music. I also have ordered the Griffin Smart Talk so i can listen to my headphones and be able to answer the phone as well however I didnt want to use it for plugging into a car stereo etc etc so i wanted a straight lead conversion.
Just a quick warning the first lead i ordered from this person was faulty, however i had also ordered 3 other leads from the same person as an after thought which were all perfect.. as they are only pennies it is worth ordering one or two spare for redundancy purposes. I decided to order 3 as backups more in case i broke one and the person stopped selling them etc etc
These leads will allow you to connect the htc to any other source including external speakers which didnt work when putting them in normally but did work when i used this cable in conjunction with it.
this cable is a trrs to trs jack plug and is used to convert a 4 pin socket to a 3 pin socket jack plug.

I've been using a pair of JVC Gummy Air on my Desire since I got it, not a single problem.

Re: TRRS Pinouts for Desire
I've used some headphones, and 2 different aux connector for the cars and all 3 work absolutely perfectly. No issues at all.
Sent from my HTC Desire

I have been using my Yuin PK3 earbuds for music since I got my Desire and it has been working without any problems.

TheOriginalKi said:
I've been using a pair of JVC Gummy Air on my Desire since I got it, not a single problem.
Click to expand...
Click to collapse
Oh yeah and I've also hooked it into the tv via a standard audio cable!

Not sure what you guys are talking about but my AIAIAI headset works fine with the Desire
Mic working too!
aiaiai.dk/headsets/tracks-headsets/tracks-headset-black.html
^those

Sennheiser PXC 250 with NR, no problems

Solving usb port mistery

Hello everyone! My name is Patryk Andrzejewski (don't try to read my name if you're not polish), and this is my first thread on XDA.
I am studing electronics on university of technology so i'm pretty well with all kind of electronic stuff.
What i'm trying to do is "x-ray" the usb port in our TG01.
My basic targets is to find way to charge the device while using USB HUB or while listening music. If it's even possible to do.
Right now I know how to connect TG01 to amplifier by 3.5mm plug. Generaly most amplifiers have high impedance input while tg01 expect low impedance earphones to switch usb port to audio output. So what we need to do is take two resistors with the same resistance around 10k Ohm and connect them both between ground and both signal channels in male 3.5mm plug of the amplifier. This should do the trick. You can experiment with resistance but it should be as high as possible to not interfere in sound quality, but if it be to big output won't swich or sound would chop on high volume.
Basic usb cable have four wires plus ground. While micro usb plug have five pins. This extra pin is used to tell device what cable is connected, hub earphones charger or pc. It can be done by two ways, in each cable this extra pin is shorted to diferent other pins. Or it's connected by resistor to ground or Vcc.
What i need to do is determine how it is in our devices and if it would be done make a cable what will allow to charge while using usb to other purposes.
I can also help with porting microusb-3.5mm cables from other devices to TG01, just what i need is this cable, it's schematic, connection route with insides picture or small donation to buy it for tests.
Or eventualy I can make solution how to do it yourself.
Right now I waiting for a pack with new empty microusb male and female plugs to do some tests.
If someone have some experience with this please share.
Also it would be great if someone will port me on to usb switch driver.
Feel free to talk to me on priv.
Thread will be updated...

Hi @patryk,
Welcome to the TG01 Forum.... especially on this particular topic - if you can find a way to get multiple function via the uUSB port simultaneously, that will be great
There have been various attempts at this before, but in practice the only route seems to be using Bluetoth for audio while either charging or using the port in host mode.
I did a piece on Brighthand a while ago on connecting an external hard drive; there have also been discussions on MoDaCo and later on XDA (down the Accessories thread.... one is here and I think there may be some earlier than that). There is a link in the XDA post to a Freescale Smiconductor chip schematic. This is supposed to be able to (externally) support multi-function usage - ntended to be used by 3rd Party manufacturers in eg. a car kit, but as yet I am not aware of any such accessories having been released. If/when available would be suitable for any of the modern crop of uUSB based evices, though I think many car makers have opted for Bluetooth connectivity instead of the older style fixed car kits with cables.

Acording to pdf from your link I'm right, its all about one resistor. It's entire possibly to do this.
Tomorrow morning tests...
Thanks
oh I cant wait so:
rid_f: >220 kOhms
rid_a: 122-126 kOhms <-- this is what we're interest in
rid_b: 67-69 kOhms
rid_c: 36-37 kOhms
rid_g: 1 kOhm
These res val has small tolerance and ar not typical.
rid_a resistance is used to switch to charge device from charger and use usb for earphones or hub!
earphones - yes, but headset - not sure I must check first where mic is connected
here it is Dummy cable schematic:

Here are some related illustrations:
Schematic of the uUSB standard audio accessory control:
View attachment 505996
Picture of the supplied Toshiba earphone adaptor pcb:
View attachment 505997
The mic is connected to pins 1 and 2 (White and bare Cu)
I have made up several 3.5mm audio adapters using Neutrik 3.5mm jacks with 10k resistors fitted from D+ and D- to 0V common:
View attachment 506008
This ensures it will switch to audio out when connecting to external speakers with or without a ground-loop isolator transformer where typically the external device will have too low an impedance for the TG01 to recognise.
Shorting out D+ (Pin 2) and D- (Pin 3) causes the TG01 to go into Charging mode.
An R from ID (Pin 4) to 0V (Pin 5) causes the TG01 to go into Host mode.

I check all of these Rid's and it seems they don't work on Tg01. No matter how i try there is working only charging or earphones never both same time.
As you say device can be forced to charge when resistor < 200 ohm is connected between D+ and D- and they are floating.
There also must be other way to do this by the driver of usb charging becouse pc link charges only when TG is on.
In TG mic an switch of headset are connected to ID pin. So this first schematic of yours is about Toshiba accesory ?
Technicaly charging while using audio out is possible becouse VBUS pin is free in headset.
I'll do some other tests tomorrow..

Hi!
Any news since February?

I will find answers on many questions by reading this document

djtonka said:
I will find answer on many question by reading this document
Click to expand...
Click to collapse
It is a good document, but iunfortunately leaves many questions unanswerable.
In Section 6.4 it shows a schematic of an Accessory Charger Adapter which is essentially what we need to achieve simultaneous charging and audio out (or other functions). It does not however give enough detail to implement. I have previously identified a Freescale chip which has been designe dto do this job, but hae been unable to identify any source from which to obtain one. In essence this is aimed at the peripheral manufacturers' -who might wish to design and market eg. a hands free car kit to which you could connect a microUSB On The Go spec device. However so far as I can discover there are no manufactureres who have as yet brought any related device to market. If anyone happens to have found anything somewhere across the globe - please shout !
Regards,
Kevin

Connecting an android phone to a car with a MOST optical audio system. Help needed!

Hi all,
I have an interesting problem to pose to the techies amongst you.
I have just managed to get my dream car and now need to integrate my phone without paying the huge sums being asked for by the car manufacturers and some aftermarket electronic suppliers (car ICE specialists too). My phone is currently a Samsung Galaxy Note 3 and the car has MOST optical audio and satnav systems.
I'm after 3 distinct, yet simultaneous, solutions, which are : -
A/ power supply to the phone
B/ HDMI or RCA output to a dash mounted 5 inch lcd screen for satnav purposes
C/ audio output to link into the car's current MOST audio system (head unit in the dashboard, also running the car's hvac, and the amplifiers are in the boot)
My first thought was to open up the USB 3 cable and to run individual wires to 3 separate plugs for each of the 3 solutions listed above. At this point many of you may be laughing at my clearly very poor understanding of modern electronics, particularly USB, and I would not argue that at all - I'm a complete dimwit here! Obviously (I think...) the clear solution is in the fact that USB can run different objectives simultaneously.
So... I run my USB 3 CABLE from the phone to a (presumably powered?) USB 3 hub and have 3 appropriate cables plugged in and running respectively to A/ a USB cigarette lighter socket, B/ an hdmi (or RCA, or composite?) plug and C/ to a standard stereo headphone jack or socket.
I don't think A/ will work because I don't see power going from the socket back through the hub and into the phone. Suggestions welcomed as I can't see how to get power to the phone at the same time as having a USB cable supplying data out. Or is there power over USB through a hub available?
B/ seems straightforward enough.
C/ the audio then needs to go to an analog to digital / wired to optical adapter and then a 2 into 1 optical switch (so I can still have the existing output from the head unit) before plugging into the amplifiers. These 2 adapters are easily available through eBay, Amazon or Maplins as far as I can see. The issue I foresee here is will the head unit still be able to control volume, fade, etc of the signal coming from the phone? If the control of the amplifiers happens via the optical cables then presumably that won't happen if I've used a switch to change the source? Would taking the output from the phone's headphone socket be of any benefit? I doubt it as the output power from there may be quite a bit higher than from the USB port...
So you can see that I clearly need some knowledgeable direction here or I will be forever going round in ever decreasing circles!
Many thanks in advance for any help given. Cheers, Mark

Esirin MTCD - external mic connection?

Hallo,
I got my new MTCD head unit. Its this one:
http://www.erisinwholesale.com/special-car-dvd/audi/erisin-es3078a-7-android-51-car-dvd-gps-dab-for-audi-a4-497.html
I have dont done much testing yet, but i want to connect my external mic first.
The HU is delivered with an small additional harness that included a external mic and a 4-pin connector on the other end. (see attached photo - connector E)
I want to cut this harness and solder a standard mic-jack onto it.
(and then desolder the internal mic)
Does anyone know the pin-out of this 4-Pin connector?!
I guess this is standard on many of the newer MTCD units?!

check with ohmeter the ohm value between gnd and signal and use similar specs mic.

Dear OP, Im very interested in you project. I have nearly the same unit but for A3. I also wanted to wait with the mic until i come up with a better solution than using the one which came with it. Do you know how to disable the standard handsfree function of the car? Now the "Mode" button always messes with the Mode of the headunit. Where is the cars' mic plugged into? How can I access this spot?
in some (i think it was russian) forum i came across the ROM wich connects via Bluetooth to the standard handsfree of the car before calling. But with the standard Rom so far i was not able to conect to it.
PS: Does your unit snap into the DIN booth like the original radio? Mine does not snap in and therefore is kinda loose

i am not sure how to measure the correct ohm value of a mic.
If i connect my multimeter to the factory ext. mic, i see 1,325 kOhm
If i connect it to my parrot mic, i see 1,660kOhm (i have attached a photo of this mic)
But anyhow, i am more interessted in the 4-pin plug, this head unit uses for the ext. mic. hook up.
As you can see on the attached photos, the lower two pins are jumpered.
And the upper two pins go to the mic.
I also found, that one of those two lower pins is a 5V supply on the head unit.
So this harness of the factory external mic seems to have some sort of switch function also...
But i am not sure, what it does...

And to answer Mighty_X´s questions:
I have no "mode" button on my head unit. Not sure, what you mean.?!
On my older MTCB unit, i just cutted the wires to the internal mic, and connected my parrot mic to the ext. mic connection.
But here, on this new Erisin MTCD, all connectors at the back of the unit are different...
regarding accuracy of fit:
The head unit didn´t fit in perfectly. Its a little bit wider at the bottom, than the original radio. If you carefully push a little harder you get it into a very good position. The cars dashboard is flexible enough for that. But thats not really a problem and its definitely not loose.

Pedaaa said:
And to answer Mighty_X´s questions:
I have no "mode" button on my head unit. Not sure, what you mean.?!
On my older MTCB unit, i just cutted the wires to the internal mic, and connected my parrot mic to the ext. mic connection.
But here, on this new Erisin MTCD, all connectors at the back of the unit are different...
regarding accuracy of fit:
The head unit didn´t fit in perfectly. Its a little bit wider at the bottom, than the original radio. If you carefully push a little harder you get it into a very good position. The cars dashboard is flexible enough for that. But thats not really a problem and its definitely not loose.
Click to expand...
Click to collapse
Thanks for your answer. I was refering to the Mode Button on the steering wheel.

Ahh, OK sorry
I only have the standard steering wheel without any buttons, so i can't comment on this

dont worry about 4pin conn, just check that the mic you want to use in head unit support that ohm input, otherwise the sound quality wont be good, just make "test-fail" until you get good result. just connect to 2 wires mic the mic you want to test...

But i do worry about this 4-Pin connector
If you connect the original ext.mic, the lower 2 pins are jumpered.
What internal effect would this have?
Is it just an input, that an ext. mic is connected?!
But why? Would the singals of the mic wont work without this input?
Or will this input maybe disable the internal mic?!
Then we wouldnt need to do the mod, by desolder or cut the internal mic on such units.
Thats just my thoughts, but i haven't done testing yet. Also i am not sure how i could figure it out exactly...

Pedaaa said:
But i do worry about this 4-Pin connector
If you connect the original ext.mic, the lower 2 pins are jumpered.
What internal effect would this have?
[..]
Thats just my thoughts[...]
Click to expand...
Click to collapse
Well, on my unit (Erisin 3047A) the ONLY reason why the lower 2 pins are "jumpered" is purely a mechanical issue: By having 4 wires and tied them together using a cable tie the two upper (small) cables are fixed in place. So: No actual use, just for mechanical reasons.
Did you have a cable tie on your 4 wires? From your pictures I cannot see it, perhaps you removed it?
Well, I just used my external micro from the installation before, and it works great.
Kind regards,
hardcoded74

Hi,
Ok, there were no reasons for my concerns.
I unsoldered the interal mic.
And then i soldered a headphone jack to the two wires of the original ext. mic harness.
The didnt touch the lower jumper wire.
And now:
It works great with my parrot mic! No echo, and really good quality in general! I am very happy now.
I also now installed a time-delay-relay for my rear view cam. Now the cam keeps going for apprx. 8 seconds, if i change to forward gears. Thats a great improvement also, that i can recommend

Pic of the modified harness

please poiint out, what headphone you used for this and the cables (by color) you connected to. (red to white for example)
thanks

Hello,
I use a PR2627 Parrot Twin Mic.
I cutted the standard ext mic and soldered a 2,5mm female jack instead of it. The white lead from the original cable goes to the "left" connection on the jack.
So the tip of the male 2,5mm pin will contact the white cable.
The black lead goes to the ground connection of the jack.
Thats it.
So, i use this Stereo mic only as a mono mic.
But it works great.
But i have to say also the original ext. mic. isnt that bad, if you disconnect the internal one.

I want to try to use the original Audi microphone. The ohmmeter says the Audi is 7,9kOhm and the mic wich came with the Erisin is 0.9kOhm. Is it possible to get good results here? What do you guys think?
I ll have to search were the wire goes wich is not to easy in Audi A3 (at least for me)
Edit: Like I thought the quality of the original mic used with the new head unit is pretty poor. dumb and very quiet. Not sure now if i get another mic, use the erisin one or maybe try a mic amplifier..

So if I understand this correct, the headunit keeps using the signal from the internal mic, even if there is an external mic connected? In essence, it gets mixed? No wonder everybody on the other end of the line is complaining that they don't understand a word I'm saying.
Is it easy to unsolder the internal mic?

HVB83 said:
So if I understand this correct, the headunit keeps using the signal from the internal mic, even if there is an external mic connected? In essence, it gets mixed? No wonder everybody on the other end of the line is complaining that they don't understand a word I'm saying.
Is it easy to unsolder the internal mic?
Click to expand...
Click to collapse
Can someone confirm this or disagree?

Mighty_X said:
Can someone confirm this or disagree?
Click to expand...
Click to collapse
You couldnt find the answer in the entire thread devoted to this issue Yes; if an an external mic input is factory, it is in parallel with the internal mic. This is a rookie design mistake.

Is there a way to change sensitivity of the external mic input? Did not find an option in the factory settings..

I unsoldered the internal mic now too. After first tests I can say say that doing that had no effect on the input sound quality or anything at all. And i found out that the internal and external mic wich came with it arethe same piece of hardware. I still wonder if there is a way to increase intensity of the mic without going over hardware amplifier. Have a kinda newer Ersisin model I guess

Faulty unit - no sound?

I have an Xtrons PF75ATTAR and it has developed a fault. It boots up fine and everything works as it should however there is no sound.
I have reinstalled the original Audi head unit and this works fine so the fault seems to lie with the Xtrons unit.
I contacted Xtrons and as I am not the original purchaser they can offer no support at all and suggested I buy a new unit. It is just still within 12-months warranty so I am trying to get hold of the guy I bought it from to see if he can arrange an RMA, however I need to try other options just in case I can't get hold of him or he won't cooperate.
I am not much of an electronics person (I have a soldering iron and a multimeter....) so I am not sure how to troubleshoot this.
The unit has a 'dongle' between the audio out on the rear of the head unit. This is encased in heat-shrink and I am not sure what it does, but is inline with the audio outs so I am wondering whether it might be this that is at fault?
Any help is appreciated
Andy

ADB100 said:
I have an Xtrons PF75ATTAR and it has developed a fault. It boots up fine and everything works as it should however there is no sound.
I have reinstalled the original Audi head unit and this works fine so the fault seems to lie with the Xtrons unit.
I contacted Xtrons and as I am not the original purchaser they can offer no support at all and suggested I buy a new unit. It is just still within 12-months warranty so I am trying to get hold of the guy I bought it from to see if he can arrange an RMA, however I need to try other options just in case I can't get hold of him or he won't cooperate.
I am not much of an electronics person (I have a soldering iron and a multimeter....) so I am not sure how to troubleshoot this.
The unit has a 'dongle' between the audio out on the rear of the head unit. This is encased in heat-shrink and I am not sure what it does, but is inline with the audio outs so I am wondering whether it might be this that is at fault?
Any help is appreciated
Andy
Click to expand...
Click to collapse
Hi there, do you have any pics of this "dongle"?
I'm just wondering if the speaker outputs have been converted to a low level output so they can be used as a line-in on an amp. If this is the case then the speaker outputs will have been spliced and effectively diverted from the loom which would result in no sound until you either use the converted outputs into a separate amp or reconnect them to the original wires so that you use the standard speaker outputs from the head unit.
I may be well of the mark here but seeing as I have just completed an install in my friends van with this same "spliced" setup, its worth checking out.

sirleeofroy said:
Hi there, do you have any pics of this "dongle"?
I'm just wondering if the speaker outputs have been converted to a low level output so they can be used as a line-in on an amp. If this is the case then the speaker outputs will have been spliced and effectively diverted from the loom which would result in no sound until you either use the converted outputs into a separate amp or reconnect them to the original wires so that you use the standard speaker outputs from the head unit.
I may be well of the mark here but seeing as I have just completed an install in my friends van with this same "spliced" setup, its worth checking out.
Click to expand...
Click to collapse
I didn't take these pictures myself, however this is the dongle.
It was working fine for about 6-months and I haven't changed anything. I got in the car one day and there was no sound. After about 20 minutes I started to hear some pops and feint audio. I stopped the car and turned the ignition off for a minute or so and then started it back up and the sound returned. The next time I got in the car there was no audio and stopping and starting didn't fix it.

ADB100 said:
I didn't take these pictures myself, however this is the dongle.
It was working fine for about 6-months and I haven't changed anything. I got in the car one day and there was no sound. After about 20 minutes I started to hear some pops and feint audio. I stopped the car and turned the ignition off for a minute or so and then started it back up and the sound returned. The next time I got in the car there was no audio and stopping and starting didn't fix it.
Click to expand...
Click to collapse
Ok, that's not what I was thinking....
That looks like the breakout for your line-out, do you run an amp with your head unit or just use the internal amp?
Your description of pops and feint audio with eventual lack of audio sounds like something has blown

sirleeofroy said:
Ok, that's not what I was thinking....
That looks like the breakout for your line-out, do you run an amp with your head unit or just use the internal amp?
Your description of pops and feint audio with eventual lack of audio sounds like something has blown
Click to expand...
Click to collapse
My car has a Bose amp (factory fit).
Any ideas how to troubleshoot?

ADB100 said:
My car has a Bose amp (factory fit).
Any ideas how to troubleshoot?
Click to expand...
Click to collapse
Ok, I'm not familiar with Audi setups but I'm guessing the Bose amp still requires a 12v remote to switch it on, usually a blue wire from the head unit. Could be worth checking that for 12v on ignition.
My PX5 unit effectively has 2 blue remote wires, one called "ANT" and one called "AMP SWITCH" or something like that..... might be worth swapping those over if you have two like I do.
How is audio supplied to the amp? Is it via the line out RCA's or via the loom/harness?
Another thing to look at, and I know this will sound super silly but on my unit a couple of the connections on the rear are similar to one another and it could be relatively easy to plug something into the wrong port. I did it and wondered why my USB didn't work! I'm sure this is not the case but still worth checking.

sirleeofroy said:
Ok, I'm not familiar with Audi setups but I'm guessing the Bose amp still requires a 12v remote to switch it on, usually a blue wire from the head unit. Could be worth checking that for 12v on ignition.
My PX5 unit effectively has 2 blue remote wires, one called "ANT" and one called "AMP SWITCH" or something like that..... might be worth swapping those over if you have two like I do.
How is audio supplied to the amp? Is it via the line out RCA's or via the loom/harness?
Another thing to look at, and I know this will sound super silly but on my unit a couple of the connections on the rear are similar to one another and it could be relatively easy to plug something into the wrong port. I did it and wondered why my USB didn't work! I'm sure this is not the case but still worth checking.
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The audio is supplied to the amp via a quad-lock connector. So the audio from the rear of the unit connects to this dongle on one side, out the other side of the dongle are four female RCA's. These are connected to four male RCA's that connect to the quad-lock connector. There are two blue wires labelled 'AMP-CON' that have male/female push-fit connectors and these are connected together - I am guessing this is the 12v to switch the amp on? There is also another blue wire labelled 'ANT' with a push-fit connector. This is connected to a green wire coming out of the antenna facra cable.
It was working and nothing has been disturbed so I am fairly sure its not been wired up incorrectly. I think something has broken...
I'll check with a multimeter that I am getting 12v on the AMP-CON cable from the back of the amp first.
Andy

OK, so armed with multimeter I decided to have a play with this earlier. It does appear that the AMP-CON wire is not delivering 12V and therefore not turning the Bose amp on.
If I disconnect the 12v wire from the dual fakra antenna adapter the sound kicks in, however the radio reception is dreadful. I believe the 12V wire is there to power an antenna signal booster integral to the car. If I measure the voltage with the 12v wire disconnected from the fakra adapter its 10.something volts, if I measure it with the 12v wire connected its 0.something volts. Is it likely this fakra adapter is faulty? It looks like a passive component?
Cheers
Andy

ADB100 said:
OK, so armed with multimeter I decided to have a play with this earlier. It does appear that the AMP-CON wire is not delivering 12V and therefore not turning the Bose amp on.
If I disconnect the 12v wire from the dual fakra antenna adapter the sound kicks in, however the radio reception is dreadful. I believe the 12V wire is there to power an antenna signal booster integral to the car. If I measure the voltage with the 12v wire disconnected from the fakra adapter its 10.something volts, if I measure it with the 12v wire connected its 0.something volts. Is it likely this fakra adapter is faulty? It looks like a passive component?
Cheers
Andy
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Ah good, I'm glad that you've narrowed it down! As far as I'm aware, these wires are 12v switched and are there simply to provide the signal for whatever device to turn on. If the AMP-CON wire has no voltage, you may just be able to use the same wire you use for your Antenna. I have done this before where I used the 12v switched wire from an antenna in the boot instead of running a remote wire the full length of the car.
I would be curious to find out why the AMP-CON wire does not supply voltage, it could be down to a broken wire somewhere or even a dodgy solder within the unit.

sirleeofroy said:
Ah good, I'm glad that you've narrowed it down! As far as I'm aware, these wires are 12v switched and are there simply to provide the signal for whatever device to turn on. If the AMP-CON wire has no voltage, you may just be able to use the same wire you use for your Antenna. I have done this before where I used the 12v switched wire from an antenna in the boot instead of running a remote wire the full length of the car.
I would be curious to find out why the AMP-CON wire does not supply voltage, it could be down to a broken wire somewhere or even a dodgy solder within the unit.
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Hi, thanks for taking the time to help out. I don't think I described the cabling correctly. The AMP-CON and the ANT come from the same pin in the connector that plugs into the rear of the head unit (one wire comes out and then it splits into two and there is a bit of heat-shrink around the join. If I disconnect the ANT cable from the green wire that comes from the fakra adapter there is sound and the cable goes +10v. If I connect it back up there is a low 'thud' as it makes contact, the sound stops and the voltage drops to 0.something. It seems the fakra adapter is dragging the voltage down, hence why I think this adapter might be faulty.
Andy

I have the same issue now. We’re you able to resolve this?

I am also having this issue.. My HU turns on. Everything works perfectly... Just no sound. None at all. No factory amp. In a 2002 Silverado. I don't know if its the internal amp or what. Ideas?