P0766

Diagnostic Chart:

Diagnostic Chart (cont'd):

Wiring Diagram:

4th clutch is applied when circuit 898 is opened at the PCM. When the PCM opens the circuit the voltage is monitored at the terminal J4A05 to check for proper circuit conditions.

DTC PARAMETERS

DTC is set when the PCM has detected the following condition twice per ignition cycle.

- Voltage monitored at terminal J4A05 (circuit 898) is less than below 2 - 2.5 volts when the 4th gear actuator is switched off electrically by the PCM.

TEST DESCRIPTION

Numbered steps below refer to numbered Steps on chart.

1. This step verifies problem is still present.

2. If the TRS 3/4 fuse is ok, check for battery voltage on fuel pump relay side of fuse with engine running or PCM in diagnostic mode.

3. This step checks for a ground in circuit 1527A. A ground in circuit 1527A will cause the TRS 3/4 fuse to fail and set DTC P0766.

4. An open in circuit 1527A will cause DTC P0766 to set. Check circuit 1527A for opens.

5. This step will determine if 1527A fault is in the circuit to the PCM or in the actuator or connector plate.

6. This step will determine if the fault is in the actuator or in the connector plate.

7. An open or a ground in circuit 898 will set DTC P0766. This step checks circuit 898 for opens or grounds.

REPAIR VERIFICATION

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

Criteria for pass:

- Engine running.

- Power present at actuators and no active faults exist 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 DTC menu of Scan tool.

- This DTC may set or intermittent 4th gear starts may be caused by a poor electrical connection at either the PCM, actuator connector plate or Under Hood Junction Block (UHJB) terminals. Wiggling connectors while performing an actuator quick test may help isolate the problem area.

Check the tightness of the female terminal grip with a spare male terminal.

When the PCM detects a fault in the circuit (open, ground, short) the PCM will open the circuit internally to protect the circuit.

- An open circuit will probably also set a P0732, P0733, DTC P0783 4th Gear Stuck On, and a DTC P0741 - No TCC. A grounded circuit 898 will probably also set a DTC P0734 - No 4th Gear.