Clear Error Codes: How-To Guide

Hello,

I have an Audi 100, type 44, 2.5 TDI, manufactured in 1990 (engine 1T). I can now read the error memory using an LED, but can anyone tell me how to clear it?

I've already tried several things: disconnecting the control unit for a night, removing fuses (21, 26), but none of it worked. The system still shows the old error code 4422 (see the post below).

Sure, no problem. Here's the translation:

'Thank you in advance.'
Bjoern.