P0746

Diagnostic Chart:

Wiring Diagram:

During normal driving modes the PCM/TC adapts line pressure to prevent clutch slip and harsh shifts. This is accomplished by modulating the pressure control solenoid ground (1530) to raise or lower pressure. Open circuit = high pressure, grounded circuit = low pressure. When the PCM opens the circuit the voltage is monitored to check for proper circuit conditions.

DTC PARAMETERS
DTC P0746 is set when the PCM has detected voltage monitored at terminal J4A03 (circuit 1530) is less than 2 - 2.5 volts when the pressure control solenoid is switched Off electrically by the PCM, twice per ignition cycle.

TEST DESCRIPTION
Numbered steps below refer to numbered steps on chart.
1. This step verifies problem is still present.
2. If the TRS LP fuse is OK, check for battery voltage on fuel pump relay side of fuse with engine running.
3. This step checks for a ground in circuit 1525. A ground in circuit 1525 will cause the TRS LP fuse to fail and set DTC P0746.
4. A faulty solenoid or connector plate could have blown the TRS LP fuse. This step checks for low resistance.
5. An open in circuit 1525 will cause DTC P0746 to set. Check circuit 1525 for opens.
6. This step will determine if fault is in the circuit to the PCM, or in the solenoid or connector plate.
7. This step will determine if the fault is in the solenoid or the connector plate.
8. An open or a ground in circuit 1530 will set DTC P0746. This step checks circuit 1530 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 solenoids and no active faults exist for this solenoid.

DIAGNOSTIC AIDS
^ This DTC may set or intermittent harsh upshifts may be caused by poor electrical connection at either the PCM, solenoid connector plate or UHJB terminals. Wiggling connectors while performing an actuator quick test may help isolate the problem area.
^ No 2nd, 3rd, 4th gear 732, 733, 734 DTCs set if circuit grounded: low line. (Will not shift out of first.)
^ If circuit is open = high line pressure.
When the PCM detects a fault in the circuit (open, ground, short) the PCM will open the circuit internally to protect the circuit.