Quote Originally Posted by wolfe2118 View Post
Who needs a CEL?? No, you don't need the A8 cluster at all. Connect the yellow C10 on your ecu to the yellow T10/10 on the body plug of the B5. You may need to get the brown plug from an A8 since the B5 doesn't have the same ECU plugs or you can just pull a unused pin from one of the ecu connecters and use it to slide directly over the C10 pin. That's what I did which reminds me that I need to get that brown plug so I'm not stranded if my tach signal falls out somehow.
Patient is a a B3 not B5. So C10 is the important wire from the ABZ. Is this a ground control? It's not a 12v feed to trigger the CEL? Right. Thanks.