VCDS and TCU fault codes

[mor]

Hi,

I recently paid for a TCU tune on my Audi, to be flashed at home.

Their software is not able to flash my car because of supposed TCU error codes.

Mind you, the car drives fine and displays no check engine or other lights.

I’m not against buying a VCDS since I like to work on my cars anyways, but can VCDS find error codes that aren’t setting off a warning light?

Thanks!

 

[Sebastian]

Their software is not able to flash my car because of supposed TCU error codes.

Talk to the tuner/supplier about this matter.

...but can VCDS find error codes that aren’t setting off a warning light?

Of course, that is the whole purpose of self diagnostics in the first place.

 

[mor]

I did talk to them, I found them pretty abrupt and quick to say the flasher and tune are fine. That’s why I came here before going down a rabbit hole, this is my first VAG car and from other brands just kind of came to expect that any significant problem would trip a warning light so you’d know to scan the car.

 

[Sebastian]

Update/flash pre-conditions are unrelated to any MIL, but this is pretty much guessing w/o actual data from the vehicle. If you have access to a VCDS system, we can certainly take a look but realistically this is between you and your tuner/supplier.

 

[SaVAGeSoot]

I did talk to them, I found them pretty abrupt

Sounds like you should be asking for a refund

 

[Dr Sheldon]

I’m not against buying a VCDS since I like to work on my cars anyways, but can VCDS find error codes that aren’t setting off a warning light?

The answers are simple

I would not "tune" and ECU or TCU if it had Fault Codes in. I have the absolute right to rely on knowledge and discretion. Your tuner is bang on correct !!

Any decent self respecting "Tuner" will first look for these fault codes before he moves forward to doing the "tune"

If there is a Fault Code stored then there is a fault. That fault will likely get worse and you then have the opportunity to blame the tuner and his work.

There are many faults that will set a warning light and many that will not - Fact !

Some faults MUST set off a warning light, this will be a legal requirement, for example a misfire, most things emissions related as a general guide will ping up a light and maybe limp home.

Engine / Emission faults are governed by Laws. Gearboxes ? Not so much !