Inspection and Verification

NOTE: If any concerns are noted with the speedometer, stoplamps, or horn, address those concerns by referring to the appropriate service repair articles before continuing speed control diagnosis.

Verify the customer concern by operating the speed control system.

NOTE: Any aftermarket modifications, including but not limited to those listed below, may cause the speed control to not operate correctly:

Any wiring or lamp modifications affecting the brake lamp operation
LED brake lamps
Non-factory installed trailer wiring
Radios (speed sensitive, auto mute)
Remote starters and alarms
Lighting and electrical accessory modifications

Visually inspect for obvious signs of mechanical or electrical damage:
- Visually inspect the speed control actuator and accelerator controls.
- Visually inspect the speed control cable without removing it and ensure smooth cable operation. Inspect the speed control cable connection to the throttle body.
- Visually inspect the accelerator cable without removing it and ensure smooth cable operation. Inspect the accelerator cable connection to the throttle body. Also check for cable interference with the carpet, bulkhead grommet, insulation and instrument panel wiring.

Visually inspect for obvious signs of mechanical and electrical damage.

VISUAL INSPECTION CHART

Mechanical	Electrical
Speed control actuator cable Throttle linkage	Smart junction box (SJB) fuses: 17 (15A) 27 (10A) Wiring harness Loose or corroded connections Speed control deactivator switch Stoplamp switch Speed control switches Powertrain control module (PCM) Speed control actuator Bulb

If the fault is not visually evident, go to the SELF-TEST DIAGNOSTICS .