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For 1990-2009 cars only

DTC P0702 - Transaxle Control System Low Voltage


Object Number: 870967  Size: MF

Circuit Description

Each transaxle solenoid (TCC, pressure control, shift 2, shift 3 and shift 4) ground is controlled independently by the powertrain control module (PCM). However, the PCM also controls ignition voltage simultaneously to all 5 solenoids whenever the fuel pump relay is commanded ON. DTC P0702 sets when the PCM detects low feedback voltage to all 5 solenoids when the engine is running and the fuel pump relay is commanded ON.

DTC Parameters

DTC P0702 will set if all 5 transaxle solenoid (TCC, pressure control, shift  2, shift 3 and shift 4) feedback voltages are less than 1.25 volts when:

    • Engine run time is greater than 1 minute
    • Ignition voltage is greater than 9.5 volts
    • Engine speed is greater than 300 RPM
    • Fuel pump relay is commanded ON

DTC P0702 diagnostic runs continuously once the above conditions have been met.

DTC P0702 is a type A DTC for 2000, type B for 2001*.

*Applicable to vehicles built after June 2000.

Diagnostic Aids

To locate an intermittent problem, use Scan tool to command TRANS. SOLENOID POWER On with ignition ON and engine OFF. Monitor all 5 transaxle solenoid LOW VOLT or OPEN tests. When a fault, open or short to ground, exists causing loss of power to all solenoids, the scan tool will display TEST FAIL for each LOW VOLT and OPEN solenoid test.

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 ms whenever the ignition is turned ON and the device is being commanded OFF via the scan tool or PCM.

Check for a loose connection at the transaxle solenoids connector located on top of the transaxle.

If DTC  P0702 is active, vehicle will exhibit 4th gear starts, hydraulic backup/high main line pressure.

DTC P0702 Table


Object Number: 890203  Size: FP