I let someone borrow my chipped ECU today. She had a '99 5-speed FWD car (I have a '98.5 Quattro Tiptronic and the chipped ECU is running '99.5 software) so I recoded the ECU when I put it in her car. That worked just fine, but when I put it back in my car it would not accept my old code! I tried more than once, rebooted my computer, turned the ignition off and on, did everything but disconnect and reconnect the ECU but it just kept coming back to the same code (hers)! Thank God I always carry my original ECU in the trunk in case of emergency.

Is there a limit to how many times these things can be recoded? I will be contacting APR on Monday for assistance, but I was hoping someone here might know (and let it serve as a warning to others if in fact this is true).

Thanks,
Paul

 

Don't you sometimes need a login before recoding?

 

Before I took the ECU out of my car I wrote down the code. I also wrote down the code from her car (06001) before I removed her ECU so I could use it to code my ECU. The code I had written down for my car was 06521. This was incorrect. I must have swapped the 5 and 2 because the correct code for my car is 06251. Thank God it didn't take!

When I put it in her car I was able to change it without a login. However after a login I was only able to set the 5 (06251 did nothing but 06051 worked). Problems have been reported changing more than one digit at a time, so that's why I tried the latter. I still cannot set the 2. I even tried turning off the key for a few minutes, logging in again, but no luck. So I am halfway there.

Interesting that you can "downgrade" without logging in, but you have to log in to "upgrade"! I mean, it's an ECU for goodness sakes!! Are they afraid I'm gonna perform an unauthorized drivetrain upgrade to my car??

"Hah, this'll get him! He can bolt on Quattro and an automatic transmission all he wants, but good luck setting the ECU to match!"

I have a few more things I want to try, such as unplugging the ECU before trying again, etc., but I ran out of light so had to put my factory ECU back in again for now. I don't want to run it with the wrong code. According to my Bentley manual, improper coding could cause:

- Performance problems (e.g. jerky shifting, abrupt load changes, etc.)

- Increased fuel consumption

- Elevated exhaust gas values (not sure if they mean EGT or emissions)

- False malfunctions stored in DTC memory

- Reduction in transmission service life

Paul

 

Well I tried again today and found that after logging in I could recode to 06001, 06201, or 06051, but NOT 06251. Whaaat?? It did have that code at one time!

I talked to Brett at APR and he told me to send it in and they will see what they can do.

Paul

 

I've switched mine from FWD to quattro and back to debug a computer problem (swapping ECU between cars where one was FWD).

Worked fine.

 

I can switch between FWD and Quattro at will if it is set for 5-speed. If set for auto trans/Tiptronic I can only do FWD. Likewise if it is set for FWD I can switch transmission settings at will. It just will not allow BOTH Quattro and auto trans/Tip.

I am running an old beta version of the APR software that later became v3.1. Brett thinks the beta version I am running may have been based on a version of Bosch code that for some reason will not allow this particular combination.

The reason the code was there before was because the ECU had been previously coded before the beta software was loaded (the ECU coding is not stored on the flash ROM that is replaced when you install a chip, it is stored elsewhere).

Paul

 

Both auto/tip