Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Torque Converter Clutch (TCC) Check

Torque Converter Clutch (TCC) Solenoid Circuit Check:




Torque Converter Clutch (TCC) Solenoid Circuit:






Circuit Description:
The TCC solenoid is a normally open exhaust valve. The PCM activates the solenoid by grounding CKT 422 with an internal quad-driver.
The PCM continually monitors the TCC circuit for either low or high voltage depending on the commanding state of the circuit. A DTC will set if a fault is detected.
For example: If command TCC solenoid "ON," the voltage on that circuit should drop when the solenoid is grounded, if the voltage stays up for 2 seconds, a DTC will set. If the TCC solenoid is "OFF," the voltage on the circuit should remain higher if the voltage drops for 2 seconds, a DTC will set.

Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.

1. This test checks for a shorted, internal transmission harness or TCC solenoid.
2. This test checks power supply to the TCC solenoid.
3. This test checks CKT 422 for a short to ground.
4. This test checks the PCM ability to control the TCC solenoid.

Diagnostic Aids:
Check all connections at the transmission pass-thru connector.

If OK, refer to 'PCM Intermittent Diagnostic Trouble Codes or Performance" or "Symptom Diagnosis".

Some slight TCC slip is normal.