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For 1990-2009 cars only

DTC P0708 - Transaxle Range Switch Circuit High Voltage


Object Number: 870993  Size: MF

Circuit Description

The transaxle range switch determines which gear position has been manually selected. The powertrain control module (PCM) determines this gear selection by detecting a combination of opens and grounds at the four switch, A, B, C and D, inputs of the transaxle range switch. When a switch is open, the PCM code input will be high, near ignition voltage. When the switch is closed, the PCM code input will be low, 0 volts. The specific combinations of highs and lows, opens and grounds at switch, for the four code inputs at the PCM denote which gear position has been selected. Only one combination is possible for each manual gear selected. DTC P0708 sets when all 4 PCM code inputs are high, near ignition voltage, indicating four open circuits.

DTC Parameters

DTC P0708 will set if the PCM has detected all high transaxle range switch code inputs, A, B, C and D when:

    • Condition exists for longer than 0.5 seconds
    • Condition exists twice in one ignition cycle
    • Ignition voltage is greater than 9.5 volts

DTC P0708 diagnostic runs continuously once the above conditions have been met.

DTC P0708 is a type A DTC.

Diagnostic Aids

If DTC P0708 is active, the PCM will command the transaxle to start out in 2nd gear.

This DTC will set due to a disconnected switch.

Check the tightness of the transaxle switch harness connector and transaxle switch to transaxle case bolts. Each switch ground uses the switch case to transaxle case as a ground path.

Use Scan tool to verify that correct PRNDL gear positions are read.

Refer to DTC P0705 Diagnostic Aids for a gear select vs. pin grounded chart.

P0708 Table


Object Number: 890210  Size: FP