Hi all

My 04 GT has developed a new issue where some of the buttons on the infotainment are inoperable.

I am almost certain that the fault lies in the infotainment head unit but before I commit to buying one I thought I'd test the opinions of the learned community on this forum.

If I open the car with "my" key the screen displays whatever it was on the last time the car was on.

If I open the car with the wife's key the screen displays the last thing that was on when that key was last used.

If I open the car with either key but select the guest login the screen opens on the air con settings (which work).

In all instances, no matter the key or the user profile or the menu I am in (nav, settings, traffic etc) the two top left buttons next to the screen do not work, nor do the radiio/TV button, the air con button, or the trip button.

All other buttons work as do the rotary dials.

I do have some fault codes regarding the passenger side seat climate which I think is because the passenger side buttons on the head unit next to the screen don't work.

If I use the guest profile the air con settings work apart from the top two left hand screen buttons and if I click the nav button (for example) to come away from the air con settings, I cannot then get back into the air con settings.

The unit had the odd glitch but a soft reset would often make the air con work again, but not any more.

I have tried a soft reset several times as well as battery disconnects and still no change.

I removed the head unit for several hours and tried again hoping that somehow it would fix itself, but no joy.

I am therefore, as I say, almost certain the head unit has fallen over.

However, I do wonder if any of you here concur with that, or have any suggestions to enable a fix somehow?

Thanks all

Gaz

 

Good afternoon mate, I also have a problem with my infotainment unit, I was looking at people on the internet in England, Romania, Poland, Spain... who were dedicated to fixing them but in the end I decided to go to the workshop that installed the carplay for me that I have taught on several occasions that I have installed.

After reviewing it because it did not always give the problem, they determined that it was the power supply.

My problem was that from time to time the screen would go black and the buttons would not always respond. Instead the carplay always worked.

We are waiting for the new power supply to be able to replace it, so this is what I can tell you so far in case it works for you.

 

It sounds like you've done some troubleshooting already, so good on ya mate. Based on what you've described, it does seem like the head unit might be the culprit, but it's always a good idea to get a second opinion before committing to buying a new one.

One thing you could try is checking the wiring harnesses that connect to the head unit. Sometimes, loose or damaged connections can cause weird issues like this. If everything looks good there, then yeah, you might just need a new unit.

As for advice, I'd say just make sure to do your research before buying a replacement head unit. You don't want to end up with a unit that's not compatible with your car or doesn't have all the features you need

 

Yeah. I don't intend going down the aftermarket BenHur or Android route, just a good used one will do me fine.

 

have you scanned with vcds the head unit?

 

Yes I have and no faults but I am fairly sure that vids only tests the canbus so I am still hopeful it is just the head unit has an internal issue

 

@Jinxgj ,
May I suggest that you remove the head unit from the vehicle again and do a bench test, you will only need 12 volt power to test, ground/negative to the body of the head unit, positive to the 10 amp fuse at the rear of the unit, no other modules from the vehicle are needed, this way you can test that it is in fact the head unit and not another item in the vehicle causing the fault, I have seen this before with a local shop working on a 2005 GT, he called me for help, and I went to him with both the NAV disc drive and the CD changer, the NAV drive solved his issues, I would also check that all buttons move freely and that non are stuck, even the AC temp button on and above the unit.

During the bench test, all buttons will function as the should, the screen will just display a message that the corresponding item is not available, but at least it shows that the button is functional.

Also, has anyone added anything to the head unit, such as a RVC, I have a lady from Cali who had a RVC added, things were ok for a bit, then she started having issues, dead buttons, blank screen, continuously rebooting from time to time.

My bench test videos below of fellow members units after replacing the big **** controller, and or boards.

Johnny

.

 

Thanks Johnny

will try that in the morning and let you know how I get on.

Gaz

 

OK…so after following Johnny’s advice I have bench tested the head unit and the same issues are present.

The Audio, A/C, Trip and the two top buttons on the left hand side of the screen are non responsive. I therefore think I am safe in the assumption that the head unit is at fault.

I did video it but the file is too big for here so I will have to try a different method.

Gaz


I put it on my VERY new fledgling YouTube channel…hopefully the url above will work. Please excuse the terrible camera work and lack of commentary.

 

I repaired my head unit with the folks who are specialising in VW. I think they replaced a central processor. In my case it was rebooting from time to time. That seems to be a known issue witch these units. I think technically it might be something to do with the heat recirculation which affects the electrics. They said it is one-to-one Phaeton module. Works like a charm for 1.5 years since then. Only thing they did not want to touch was the car itself, so I had to remove the unit and put it back afterwards.

To conclude, if you experience reboots (in addition to any other side issues) this is something can only be fixed by a professional who has the replacement parts.