DTC P0740

Circuit Description

The torque converter clutch (TCC) solenoid is applied when circuit 422 is grounded at the PCM. When the PCM opens the circuit, the voltage is monitored at terminal J4A02 to check for proper circuit conditions.

Conditions for Setting the DTC

DTC P0740 is set when the PCM has detected voltage monitored at terminal J4A02, circuit 422, is less than 2-2.5 volts when the solenoid is switched OFF electrically by the PCM twice per ignition cycle.

Test Description

Numbered steps below refer to numbered steps on the chart.

1. This step verifies the problem is still present.
2. If the TCC fuse is OK, check for battery voltage on the fuel pump relay side of the fuse with the engine running or the PCM in diagnostic mode.
3. This step checks for a ground in circuit 1526A. A ground in circuit 1526A will cause the TCC fuse to fail and set DTC P0740.
4. A faulty solenoid or connector plate could have blown the TRS 2/TCC fuse. This step checks for low resistance.
5. An open in circuit 1526A will cause DTC P0740 to set. Check circuit 1526A for opens.
6. This step will determine if a fault is in the circuit to PCM or in the solenoid or connector plate.
7. This step will determine if the fault is in the solenoid or in the connector plate.
8. An open or a ground in circuit 422 will set DTC P0740. This step checks circuit 422 for opens or grounds.

Repair Verification

Monitor the DTC menu Code Status for Pass Since Code Clear and Pass This Ignition Cycle. When both have passed, the repair is verified.

Criteria for pass:

• Engine running
• Power present at all actuators
• Active faults are not present for this actuator.

Diagnostic Aids

When attempting to diagnose an intermittent problem, use the scan tool* to review supplemental diagnostic information. The supplemental data can be used to duplicate a problem.

*Select MALF History and DTC status from the DTC menu of the scan tool.

• DTC P0741 may set because of a poor electrical connection at either the PCM, actuator connector plate, or UHJB terminals. Wiggling the connectors while performing a solenoid quick test may help isolate the problem area. Check the tightness of the female terminal grip with a square male terminal. When the PCM detects a fault in the circuit, an open, ground, or short, the PCM will open the circuit internally to protect the circuit.
• An open circuit will probably also set a DTC P0741.
• A grounded circuit 472 will probably also set a DTC P0742.