DTC P0746 - PC Solenoid Control Circuit High Voltage
Circuit Description
The pressure control (PC) solenoid is used to control main line pressure to the transaxle hydraulic system. The powertrain control module (PCM) pulse width modulates (PWM) the PC solenoid whenever the engine is running. The PCM controls the PC solenoid by pulse width modulating an internal driver that pulls the solenoid circuit to ground. When the PC solenoid is commanded Off, main line pressure is highest. During normal shift operation, the PCM will turn ON or OFF the 2, 3 or 4 shift solenoids and PWM the PC solenoid to prevent clutch slip and harsh shifts. The PC solenoid circuit is monitored for low and high voltage faults. DTC P0746 sets when the PC solenoid is commanded O, or PWM Off-time, and the feedback voltage at the PCM is low.
DTC Parameters
DTC P0746 will set if PC solenoid feedback voltage is less than 1.25 volts with PC solenoid commanded OFF when:
| • | Condition exists for longer than 100 milliseconds (2001)* |
| • | Condition exists for longer than 100 milliseconds, solenoid is turned Off for 1 minute, then condition exists again for longer than 100 milliseconds (2000) |
| • | Fuel pump relay is commanded On |
DTC P0746 diagnostic runs continuously with fuel pump relay commanded On and PC solenoid commanded Off.
DTC P0746 is a type D DTC.
*Applicable to vehicles built after June 2000.
Diagnostic Aids
To locate an intermittent problem, use scan tool to command TRANS. SOLENOID POWER On, while monitoring the PC SOLENOID - LOW VOLT or PC SOLENOID - OPEN test. When a fault, open or short to ground exists, the scan tool will display TEST FAIL for both tests.
The tests will fail only when the device is being commanded OFF and the voltage at the PCM is low. The tests update every 100 milliseconds whenever the ignition is turned On and the device is being commanded OFF via the scan tool or PCM.
PC solenoid resistance: 3.8-7.2 ohms
Nominal value: 4.5 ohms at 68°F
