GM Service Manual Online
For 1990-2009 cars only

Circuit Description

DTC P0730 is set when all forward gears are indicated as not available.

DTC P0730 is an indicator that all gears are being affected by the same condition.

Conditions for Setting the DTC

DTC P0730 will set when the PCM has detected the following conditions:

    • Vehicle speed is 0.
    • Steady moderate throttle.
    • The input shaft speed is above 756 RPM.
    • The PCM commanding 1st, 2nd, 3rd, or 4th gears results in no accurate input shaft speed pull down.

Test Description

Check for DTC P0745. If present, repair first and road test the vehicle. If no diagnostic trouble codes are present then check for the following items:

    • The transmission range switch failed or the harness was wired incorrectly.
    • The transaxle may be hydraulically in neutral and the selector switch indicates a forward gear.
    • The shift cable is misadjusted.
    • The manual valve is disconnected.
    • Verify the VSS/ISS sensor using the scan tool.

Repair Verification

Monitor the DTC menu Code Status for Pass Since Code Clear and Pass This Ignition Cycle. When both have passed, the repair is verified.

Criteria for pass:

    • Input speed is greater than 0.
    • Vehicle speed is greater than 5 km/h (3 mph) for 0.5 seconds.