1989 Pontiac Bonneville • 6 cylinder FWD Automatic • 114,687 miles

What is quad driver code 26 on 1989 pontiac bonneville
Tom stroup jr
March 21, 2011.

Fault in TCC circuit ie. Transmission most likely wiring problem. Will need to have scanned to find fault

Mar 21, 2011.
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.

Mar 21, 2011.