1989 Pontiac Bonneville Repair Question
Fault in TCC circuit ie. transmission most likely wiring problem. will need to have scanned to find fault
18,416 answers provided
The quad drivers are the grounding transisters that control actuators under the control of the ECM. There are 4 of them and each one could be operating more than one actuator. The code is usually the result of one of the quad drivers being overloaded from one of it's actuators drawing too much current. the TCC solenoid is one of many different actuators that could be causing the problem and it could be a long process trying to figure out which one is causing it.
14,713 answers provided