Aisin 81-40LE - Automatic Transmission (Non European Emissions)

DTC P0748 (Non European Emissions)

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0748 Pressure Control (PC) Solenoid Control Circuit

Conditions for Setting the DTC

* The transmission control module (TCM) detects that the feedback voltage is greater than 4.9 volts and detects the detection 500 milliseconds continuously. The pressure control solenoid (PCS) circuit is short to battery.
* The TCM detects that the feedback voltage is less than 70 mV for 70 milliseconds and detects the 12.5 seconds continuously. The PCS circuit is short to ground or open.

Action Taken When the DTC Sets

* TCM will request the illumination of the hold lamp and store the DTC when the TCM detects a failure on the 1st ignition cycle
* No lockup control
* No engine torque reduction control
* No engagement pressure control
* No 4th gear
* No self-learning control
* After failure decision: emergency mode

Conditions for Clearing the DTC

* The TCM turns off the hold lamp when no further failures are detected on the next ignition cycles.
* The scan tool can clear the DTC from the TCM history.
* The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.
* The TCM detects the feedback voltage is between 70 mV and 4.9 volts for 12.5 seconds continuously.

Cause of Failure

* Wiring harness or connector between PCS and TCM
* PCS
* TCM