P076

Circuit Description

The transaxle pressure control solenoid regulates pressure to maintain a desired transaxle line pressure under varying operating conditions. The PCM sends a Pulse Width Modulated (PWM) signal (varying duty cycle signal) to the transaxle pressure control solenoid in order to control the line pressure.

A PCM internal current monitor is provided as a feedback to determine actual transaxle pressure control solenoid current drawn. Current draw is proportional to transaxle line pressure. If commanded vs. actual current draw is different by more than the calibrated value or if the transaxle pressure control solenoid is energized at 100% duty cycle for 3 minutes or more, Code P076 is set.

Test Condition(s)

1. Codes P016, P086 and P089 not set.
2. Engine running.

Failure Condition(s)

1. Difference between commanded and actual transaxle pressure control solenoid current 0.16 amps or greater for 1 second.
OR
2. Transaxle pressure solenoid energized at 100% duty cycle for 3 minutes or more.

Action Taken

1. PCM turns 'ON' the 'SERVICE ENGINE SOON' MIL.
2. PCM deenergizes the transaxle pressure control solenoid.
3. Torque management is disabled.
4. Transaxle shift adapts are maintained at current levels.

Notes on Fault Tree

1. Checking for an open in the transaxle pressure control solenoid circuitry. If resistance is 8 ohms or greater, there is an open in circuitry.
2. Checking for a short to ground in the transaxle pressure control solenoid circuitry. If resistance is 100 ohms or less, there is a short to ground in the circuitry.
3. Transaxle pressure control solenoid circuitry is OK, so fault is either intermittent or the PCM is bad.
4. If the resistance measures greater than 8 ohms check for an open inside the transaxle on CKT 1228, CKT 1229 or in the transaxle pressure control solenoid. If resistance is 8 ohms or less, check for an open between C130 and the PCM in CKT 1228 or 1229.
5. If the resistance measures 100 ohms or greater, check for a short to ground between C130 and the PCM in CKT 1228 or CKT 1229. If resistance measures less than 100 ohms check for a short to ground inside the transaxle in CKT 1228, CKT 1229 or in the transaxle pressure control solenoid.