GM Service Manual Online
For 1990-2009 cars only

Cruise Control Disabled


Object Number: 871370  Size: MF

Circuit Description

The cruise control system can be disabled due to a number of conditions that may or may not set DTC P1584. Under a properly working cruise control system, normal driver commands such as turning the cruise control switch Off or depressing the brake pedal will NOT set this DTC. However, the driver may induce this DTC if the gear shift lever is placed in neutral while cruise is engaged. DTC P1584 sets when the powertrain control module (PCM) disables cruise control because any one of the following conditions listed under DTC parameters occurred while in cruise control mode.

Conditions for Setting the DTC

DTC P1584 will set if the PCM disables the cruise control clutch due to any of the following conditions occurring while in cruise control mode:

    • The gear position is out of range (trans range switch indicates P, R, N, or 1st) auto only
    • The transaxle range switch position is invalid (auto only)
    • The cruise set speed is greater than 161 km/h (100 mph) or less than 40 km/h (25 mph)
    • The vehicle speed is less than 32 km/h (20 mph)
    • The engine speed is less than 950 rpm or greater than 6500 rpm
    • Traction control is active
    • Vehicle acceleration is greater than 16 km/h/second (10 mph/second)
    • Vehicle deceleration is greater than 6.5 km/h/second (4 mph/second)
    • Cruise set speed differs from actual vehicle speed by greater than 24 km/h (15 mph) for 10 seconds or greater than 32 km/h (20 mph) instantaneously
    • The ignition voltage is less than 10 volts or greater than 16 volts
    • The engine coolant temperature is greater than 118°C (244°F) (overheat condition)

DTC P1584 diagnostic runs continuously in cruise control mode.

DTC P1584 is a type D DTC.

Diagnostic Aids

Use the scan tool Failure Record information to help diagnose driver induced cruise disable vs. cruise disable due to a system failure. Inspect the DISABLE BITS located toward the bottom of the Failure Record to determine the cause.

Make sure no transaxle range switch (auto only) or vehicle speed DTCs are present. Diagnose those DTCs first if any are set.

Make sure VEHICLE SPEED reads correctly on scan tool and that no vehicle speed DTCs are present. Make sure SPEED NOISE = NO under the transmission data display table (auto only) while the vehicle is driven. This will indicate if an intermittent output speed sensor circuit fault is occurring.