- Turn ignition switch to RUN position. Turn on cruise control. Check voltage at Pink/Black wire terminal of cruise control switch connector. If battery voltage is present, go to next step. If voltage is not present, replace IGN/GAU fuse or repair Pink/Black wire.
- Check voltage at Gray wire terminal of cruise control switch connector. If voltage is not present, replace cruise control switch. If battery voltage is present, check voltage at Gray wire terminal of brakelight switch connector. If voltage is not present, check Gray wire and brakelight switch connector.
- If battery voltage is present, check voltage at Gray wire terminal of cruise control module connector. If voltage is not present, repair Gray wire. If battery voltage is present, check voltage between Gray and Black wire terminals of cruise control module connector.
- If voltage is not present, repair Black wire. If battery voltage is present, check voltage at Gray/Black wire terminal of brakelight switch connector. If battery voltage is present, go to next step. If voltage is not present, adjust brakelight switch. See «BRAKE & CLUTCH RELEASE SWITCH/VALVE ADJUSTMENT»(ref-30176-S06827987962001010900000) under ADJUSTMENTS. If brakelight switch cannot be adjusted, replace brakelight switch.
- Check voltage at Gray/Black wire terminal of cruise control module connector. If voltage is not present, repair Gray/Black wire. If battery voltage is present, check voltage at Dark Blue wire terminal of cruise control switch connector.
- If battery voltage is present, replace cruise control switch. If voltage is not present, check voltage at Dark Blue wire terminal of cruise control switch connector while depressing and holding SET switch. If voltage is not present, replace cruise control switch.
- If battery voltage is present, check voltage at Dark Blue wire terminal of cruise control module connector while depressing and holding SET switch. If voltage is not present, repair Dark Blue wire. If battery voltage is present, check voltage at Dark Green wire terminal of cruise control switch connector while depressing and holding RESUME/ACCEL switch.
- If voltage is not present, replace cruise control switch. If battery voltage is present, check voltage at Dark Green wire terminal of cruise control module connector while depressing and holding RESUME/ACCEL switch. If voltage is not present, repair Dark Green wire.
- If battery voltage is present, disconnect cruise control module connector. Check resistance between Dark Blue/White and Black wire terminals of cruise control module connector. If resistance is greater than 55 ohms, go to next step. If resistance is less than 30 ohms, go to step 11). If resistance is 30-55 ohms, go to step 12).
- Disconnect cruise control servo connector. Check resistance between Dark Blue/White and Black wire terminals of cruise control servo connector (servo side of connector). If resistance is greater than 55 ohms, replace cruise control servo. If resistance is less than 55 ohms, repair Dark Blue/White wire.
- Disconnect cruise control servo connector. Check resistance between Dark Blue/White and Black wire terminals of cruise control servo connector (servo side of connector). If resistance is less than 30 ohms, replace cruise control servo. If resistance is greater than 30 ohms, repair Dark Blue/White wire.
- Check resistance between Light Green and Black wire terminals of cruise control module connector. If resistance is greater than 55 ohms, go to next step. If resistance is less than 30 ohms, go to step 14). If resistance is 30-55 ohms, go to step 15).
- Disconnect cruise control servo connector. Check resistance between Light Green and Black wire terminals of cruise control servo connector (servo side of connector). If resistance is greater than 55 ohms, replace cruise control servo. If resistance is less than 55 ohms, repair Light Green wire.
- Disconnect cruise control servo connector. Check resistance between Light Green and Black wire terminals of cruise control servo connector (servo side of connector). If resistance is less than 30 ohms, replace cruise control servo. If resistance is greater than 30 ohms, repair Light Green wire.
- Check resistance between Light Blue/Black and Tan wire terminals of cruise control module connector. If resistance is greater than 25 ohms, go to next step. If resistance is less than 15 ohms, go to step 17). If resistance is 15-25 ohms, go to step 18).
- Disconnect cruise control servo connector. Check resistance between Light Blue/Black and Tan wire terminals of cruise control servo connector (servo side of connector). If resistance is greater than 25 ohms, replace cruise control servo. If resistance is less than 25 ohms, repair Light Blue/Black or Tan wire.
- Disconnect cruise control servo connector. Check resistance between Tan and Black wire terminals of cruise control module connector. If resistance is greater than 15 ohms, replace cruise control servo. If resistance is less than 15 ohms, repair Tan wire.
- Raise and support vehicle with drive wheels off of ground. Start engine. Shift transmission into Drive. Check AC voltage between Yellow and Black wire terminals of cruise control module connector. If AC voltage is present, repair vacuum leak in cruise control system. If voltage is not present, check DRAC. See DRAC (SPEED SENSOR BUFFER) INOPERATIVE.
Home/GMC/Sonoma Syclone/GMC Sonoma Syclone (1991-1992)/Repair manual/Cruise Control Systems/Cruise Control Does Not Engage
Contents
Section: Cruise Control Systems- Description & Operation
- Description
- Cruise Control Module
- Cruise Control Switch
- Set/coast
- Resume/accel
- Servo Assembly
- Astro, Bravada, Safari, Sonoma, Syclone, Typhoon & "s" & "t" Series Blazer, Jimmy & Pickup
- Suburban, Van & "r" & "v" Series Blazer, Jimmy & Pickup
- Lumina Apv, Silhouette & Trans Sport
- Brake & Clutch Release Switch/valve
- Brake & Clutch Release Switch/valve Adjustment
- Astro, Safari, Sonoma, Syclone, Typhoon & "s" & "t" Series Blazer, Jimmy & Pickup
- Bravada
- Cruise Control Does Not Engage
- Drac (speed Sensor Buffer) Inoperative
- Cruise Control Does Not Disengage Using Brake Pedal
- Speed Sensor & Buffer
- Source Vacuum Check
- Servo Vacuum Valve Check
- Servo Vent Valve Check
- Brake Release Valve Test
- Wiring Diagrams
- Abbreviations
- Accessory Drive Belts
- Adjustments
- Anti-Lock/traction Control
- Application
- Automatic Trans
- Auxiliary Emission Control Systems
- Basic Trouble Shooting
- Brakes
- Charging System
- Check Lists
- Clutches Manual & Hydraulic
- Computer Relearn
- Cruise Control Systems
- Diagnostic Connector Locations
- Differentials & Drive Axles
- Door Locks & Anti-Theft Systems
- Driveline/axles
- Driveshaft & Universal Joints
- Electrical
- Electrical Component Locations
- Emission Applications
- Engine
- Engine Performance
- Fuses & Circuit Breakers
- Gauges & Instrument Panels
- General Servicing - All Makes
- Heated Glass/defoggers
- Heater
- Identification
- Manual & Power Steering
- Manual HVAC System
- Manual Trans
- MAP Guidelines
- Mechanical
- Mechanical - Hydraulic
- Metric Conversions
- Mirrors
- Pin Voltage Charts
- Procedures
- Removal & Installation
- Reset Procedures
- Rpo Codes
- Sensor Range Charts
- Specifications
- Starter
- Steering
- Steering Column
- Steering Column Switches
- Steering Gear
- Suspension Front
- Suspension Rear
- Testing & Diagnostics
- Theory & Operation
- Traction Control Disable
- Transfer Case
- Transmission
- Wheel Alignment
- Windows
- Wiper/washer Systems
- Wiring Diagrams - Engine Performance