TCC Stuck on

(P0740) TCC STUCK ON





When Monitored and Set Condition
- When Monitored: No Input Speed Sensor N2 - N3, CAN Bus Circuit, PCM, CAN Engine, No CAN Engine Torque and/or Shift in progress DTCs present. Must be in a valid forward gear.
- Set Condition: Engine RPM (turbine speed) is greater than 30 RPM when the engine torque is less than 100 Nm for 1.0 second.

POSSIBLE CAUSES
- TCC SOLENOID CONTROL CIRCUIT SHORTED TO GROUND
- CC SOLENOID CONTROL CIRCUIT SHORTED TO ANOTHER CIRCUIT
- INTERNAL TRANSMISSION
- TRANSMISSION CONTROL MODULE

Diagnostic Test
1. PRE-DIAGNOSTIC CHECK OUT





Note: Low fluid level can be the cause of many transmission problems. If the fluid level is low, locate and repair the leak then check and adjust the fluid level in accordance with the Service Information.

Note: Always perform diagnostics with a fully charged battery to avoid false symptoms.
With the DRB III*, read the engine DTCs. Check and repair all engine DTCs prior to performing transmission symptom diagnostics.
With the DRB III*, read and record all Transmission DTCs.

Note: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Repair as necessary.
Most DTCs set on start up but some must be set by driving the vehicle such that all diagnostic monitors have run.

Note: Verify flash level of transmission controller. Some problems are corrected by software upgrades to the transmission controller.

Note: Check for any Technical Service Bulletins that may apply.

Perform this procedure prior to Symptom diagnosis.
Continue
Go To 2

2. INTERNAL TRANSMISSION
Turn the ignition off. Disconnect the Transmission Solenoid Assembly harness connector.

Note: Check connectors - Clean/repair as necessary.

Start the engine.
With the brakes firmly applied, shift the gear selector into Drive.
Did the engine stall or stumble?

Yes>>Repair the internal transmission. Pay particular attention to the components related to the TCC. Refer to the Transmission - Service Information for the proper repair procedure.
No>>Go To 3

3. TCC SOLENOID CONTROL CIRCUIT SHORT TO GROUND





Turn the ignition off.
Disconnect the TCM C2 harness connector.

Note: Check connectors - Clean/repair as necessary. Measure the resistance between ground and the TCC Solenoid Control circuit.

Is the resistance below 100 kohms?
Yes>>Repair the TCC Solenoid Control circuit for a short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST. Verification Tests
No>>Go To 4

4. TCC SOLENOID CONTROL CIRCUIT SHORT TO OTHER CIRCUITS





With the ignition off.
Measure the resistance from the TCC Solenoid Control circuit to all other circuits at the Transmission Solenoid Assembly harness connector.
Is the resistance below 100 kohms on any circuit?
Yes>>Repair the TCC Solenoid Control circuit for a short to other circuit(s).
Perform NAG1 TRANSMISSION VERIFICATION TEST.
No>>Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST.