Torque Converter Clutch (TCC) Solenoid
- With key on, check 12-volt supply to solenoid through brake switch by backprobing terminal "A" (Purple wire) at the transmission solenoid. See Fig 1
. If voltage is not present, check circuit through brake switch from ignition circuit fuse No. F-13 (20-amp).
- Disconnect TCC harness connector and connect a DVOM to terminals "A" and "D" of the transmission connector. Raise vehicle drive wheels. Run engine in Drive to 30 MPH (48 KPH) to allow 3rd gear pressure switch to close.
- Measure resistance of solenoid with DVOM while switch is closed. If resistance is less than 20 ohms, replace solenoid.
Courtesy of GENERAL MOTORS CORP.