– Dirty transmission fluid
– Faulty shift solenoid ‘E’ valve
– Shift solenoid ‘E’ valve harness is open or shorted
– Shift solenoid ‘E’ valve circuit poor electrical connection
– Transmission will not shift gears.
The ECM uses the signals from the Throttle Position Sensor and Air flow Meter to monitor the engagement condition of the lock up clutch. Then the ECM compares the engagement condition of the lock up clutch with the lock up schedule in the ECM memory to detect mechanical trouble of the shift solenoid valve SLU, valve body, torque converter clutch and automatic transmission assembly