Diagnostic Aids
| • | In order to avoid a misdiagnosis, inspect for proper operation of the brake lamps. Refer to Exterior Lighting Systems Description and Operation . |
| • | For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections . |
| • | Electromagnetic Interference on the vehicle speed sensor signal circuit may cause erratic cruise control operation. |
Conditions for Enabling Cruise Control
| • | The CRUISE NOT READY message is not illuminated in the DIC. |
| • | The vehicle speed is greater than 40 km/h (25 mph). |
| • | The vehicle is not in PARK, REVERSE, NEUTRAL, or 1st gear. |
| • | The system voltage is within 9.2 volts and 16 volts. |
| • | The park brake is released. |
| • | The forward looking sensor (FLS) is radiating and the adaptive cruise module (ACM) has identified acceptable stationary or moving objects. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference : Cruise Control Schematics Connector End View Reference: Cruise Control Connector End Views or Engine Control Module Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the Cruise Control Switch parameter display On? | -- | Go to Step 3 | Go to Step 5 |
3 |
Does the Cruise Control Switch parameter display Set? | -- | Go to Step 4 | Go to Step 9 |
4 |
Does the Cruise Control Switch parameter Display Resume? | -- | Go to Diagnostic Aids | Go to Step 9 |
Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 11 | |
6 |
Does the voltage measure at or near the specified value? | B+ | Go to Step 7 | Go to Step 8 |
7 | Test the cruise control switch signal circuit for an open or for a short to ground between C7 and the BCM. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
8 | Test the cruise control switch signal circuit for an open or for a short to ground between C7 and the cruise control switch. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 9 |
9 | Inspect for poor connections at the harness connector of the cruise control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
10 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
11 | Repair the open, the high resistance or the short to ground in the cruise control switch supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | -- | Go to Step 14 | -- |
12 | Replace the cruise control switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
13 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 14 | -- |
14 | Operate the vehicle within the conditions for cruise control operation. Does the cruise control system operate properly? | -- | System OK | Go to Step 2 |
