95 1/2 Model

This Diagnostic Trouble Code (DTC) flashes the "CHECK TRANS" Indicator and does not set the Backup Mode.




Circuit Description
- The Torque Converter Clutch (TCC) Solenoid is a simple "ON"/"OFF" Solenoid connected to the Adapter Case Valve Body. When the Solenoid is energized by the Transmission Control Module (TCM), it opens a fluid port. When the port is open, line pressure actuates the converter Clutch Control Valve which engages the Torque Converter Clutch by exhausting the fluid. The TCM engages the Torque Converter Clutch only when all of the following condition exist:
1. The Transmission is at operating temperature.
2. The Brake Pedal is released.
3. The Transmission is operating in second, third or Fourth Gear.
4. The Engine is warm (more than 70°C).
5. The shift pattern requests TCC apply.
6. Shift finished.
7. No malfunction which will disable the TCC: DTC 43, DTC 55 (only short to ground).

- The Solenoid is activated by a current. This current is produced by applying a voltage to one side (the High side) and a ground to the other side (Low side).
- The High Side Driver (HSD) is a circuit of the TCM that acts as a switch between the Solenoid and the supply voltage. The High side of the TCC Solenoid is used to turn the TCC "ON" or "OFF" because the Low side is permanently connected to the ground of the Transmission. In Backup Mode or when Ignition is turned "OFF" the TCC High Side is turned "OFF".
- The TCM continually monitors the Solenoid connection to its High Side Driver for either low or high voltage.
- There is only one test of the HSD for TCC: when the Engine is cranked and the TCC is turned "ON".
- If this circuit is shorted to plus, the TCC Solenoid is constantly commanded "ON" (shifts can be firm). In First Gear the TCC is hydraulically "OFF", whatever the TCC Solenoid position. This means that the car can be driven even with the TCC shorted to voltage. The Engine could stall when the driver is braking strongly, if the car is stopped when the Transmission is still in second Gear with TCC applied.

Note: The 3-2 shifts are very firm.

Diagnostic Aids
- This diagnostic test is an electrical test done by the TCM.

- Detection Conditions:

a. The Solenoid high side connected to TCM terminal C7 is shorted to voltage or open.
b. The condition needs to be present for 0.13 seconds.

- Action After The Detection Time:
a. TCC is turned "OFF".
b. "CHECK TRANS" Indicator turned "ON".

- Recovery Conditions:
- To recover do an Ignition Cycle.








DTC 33 / Flow Charts