GM Service Manual Online
For 1990-2009 cars only

Cruise Control Direction Output Circuit Low Voltage


Object Number: 871370  Size: MF

Circuit Description

The cruise control direction circuit is used to indicate to the cruise control module the direction of the accelerator pedal (toward wide-open-throttle [WOT] or toward idle) needed to maintain cruise set speed. The powertrain control module (PCM) supplies ignition voltage on the cruise control direction circuit during cruise control operation when the needed direction is toward WOT. After the cruise set speed has been met and the direction toward WOT is no longer needed, the PCM will open the driver and the cruise control direction input at the cruise control module will go low. Under steady cruise control when no pedal movement is needed, the PCM defaults to the idle direction. The PCM monitors the cruise control direction circuit for low and high voltage faults. DTC P1582 sets when the cruise control direction circuit is commanded On, and the voltage at the PCM is low.

Conditions for Setting the DTC

DTC P1582 will set if the cruise control direction feedback voltage is less than 2.5 volts with the cruise control direction commanded On when:

    • The condition exists for longer than 500 milliseconds.
    • The cruise control direction is commanded toward wide-open-throttle.
    • The engine is running.

DTC P1582 diagnostic runs continuously with the engine running and the cruise control direction commanded toward wide-open-throttle.

DTC P1582 is a type D DTC.

Diagnostic Aids

To locate an intermittent problem, use the scan tool to perform the CRUISE CONTROL CYCLE test. The accelerator pedal should go to 50% throttle and back to idle. If a fault (a short-to-ground or an open PCM driver) occurs before the throttle reaches 50%, the accelerator will remain at rest or return to idle.

The C/C DIR. - LOW VOLT test parameter on the scan tool can also be used for intermittents. In cruise control mode, tap up the RES/ACCEL switch while monitoring the test. If a fault occurs, the scan tool will display TEST FAIL.

The voltage measured with a DVOM on circuit 1887, with the ignition On and the cruise control module disconnected, should read above 7 volts. This voltage should read ignition voltage when the CRUISE CONTROL CYCLE test is performed with the scan tool when the accelerator pedal is toward W.O.T.


Object Number: 874404  Size: FP