P0963

AF23-5 AUTOMATIC TRANSAXLE

DTC P0963

Test 1-4:

Test 5-12:

Circuit Description with AF23-5 Automatic Transaxle
The line pressure control (PC) solenoid valve (SILT) regulates solenoid modulator fluid passing through the solenoid into throttle signal pressure. The TCM uses a pulse width modulated signal in order to control the signal pressure. The TCM compares various inputs in order to determine the appropriate pressure for a given load. The TCM varies the current to the line PC solenoid valve from 0.1 amps, for maximum line pressure to 1.1 amps, for minimum line pressure. An internal current monitor within the TCM provides feedback in order to determine actual line PC solenoid valve current draw.

If the TCM detects a continuous short to voltage in the line PC solenoid valve circuit, then DTC P0963 sets. DTC P0963 is a type A DTC.

Conditions for Running the DTC
The ignition voltage is 8-18 volts.

Conditions for Setting the DTC
The PC solenoid valve feedback circuit indicates a continuous short to voltage for 2 seconds or greater.

Action Taken When the DTC Sets
^ The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL).
^ The TCM turns the Trans. Protection Mode ON. When the Trans. Protection Mode is ON, the following conditions occur:
- The transmission will operate in 5th gear when the transmission is shifted into D or I range and 2nd gear when shifted into L range.
- The line pressure is at maximum.
- The torque converter clutch (TCC) is disabled.
- The TCM freezes the transmission adaptive functions.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
^ The TCM stores DTC P0963 in TCM history.

Conditions for Clearing the MIL/DTC
^ The ECM turns off the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
^ A scan tool can clear the MIL/DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission- related diagnostic fault occurring.
^ The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM.

Test Description
The numbers refer to the step numbers on the diagnostic table.
2. This step verifies the ability of the TCM to command the line PC solenoid valve.
3. This step verifies that the automatic transmission wiring harness and the line PC solenoid valve have correct resistance.