Conditions for Enabling Cruise Control
WARNING: This page is about a different car, the 2005 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
- When vehicle speed is more than 40 km/h (25 mph).
- When PARK, REVERSE, NEUTRAL, or 1st gear is not indicated.
- When an over/undercharged battery condition does not exist.
- With normal engine rpm.
Cruise Control Inoperative/Malfunctioning
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Cruise Control Schematics | ||||
| 1 | Did you perform A Diagnostic System Check - Vehicle? | - | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 |
|
- | Go to Step 3 | Go to Step 36 |
| 3 | Probe the ignition positive voltage circuit of the cruise control module harness connector with a test lamp that is connected to the ground circuit of the cruise control module. Does the test lamp illuminate? |
- | Go to Step 4 | Go to Step 37 |
| 4 |
|
- | Go to Step 16 | Go to Step 5 |
| 5 |
|
- | Go to Step 6 | Go to Step 17 |
| 6 |
|
- | Go to Step 7 | Go to Step 19 |
| 7 |
|
- | Go to Step 8 | Go to Step 20 |
| 8 | Probe the brake ABS/TCC, cruise release switch signal circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? |
- | Go to Step 9 | Go to Step 21 |
| 9 | Press the brake pedal while monitoring the test lamp. Does the test lamp go out? |
- | Go to Step 10 | Go to Step 22 |
| 10 | Probe the stop lamp switch signal circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? |
- | Go to Step 23 | Go to Step 11 |
| 11 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? |
- | Go to Step 12 | Go to Step 24 |
| 12 | Probe the cruise inhibit signal circuit with a test lamp that is connected to B+. Does the test lamp illuminate? |
- | Go to Step 25 | Go to Step 13 |
| 13 | Use a scan tool in order to command the cruise inhibit OFF. Does the test lamp illuminate? |
- | Go to Step 14 | Go to Step 26 |
| 14 | Probe the cruise engaged output signal circuit with a DMM that is connected to a good ground. Does the voltage measure near the specified value? |
B+ | Go to Step 15 | Go to Step 27 |
| 15 | Check the speedometer for proper operation. Does the speedometer operate properly? |
- | Go to Step 28 | Go to Symptoms - Instrument Panel, Gages and Console in Instrument Panel, Gages and Console |
| 16 | Test the signal circuit that illuminated the test lamp for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 34 |
| 17 | Test the on/off signal circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 18 |
| 18 | Test the ignition positive voltage circuit for an open or high resistance between the cruise control module and the cruise control switch. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 34 |
| 19 | Test the set/coast signal circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 34 |
| 20 | Test the resume/accelerate signal circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 34 |
| 21 | Test the brake ABS/TCC, cruise release switch signal circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 29 |
| 22 | Test the brake ABS/TCC, cruise release switch signal circuit for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 29 |
| 23 | Test the stop lamp switch signal circuit for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 30 |
| 24 | Test the stop lamp switch signal circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 30 |
| 25 | Test the cruise inhibit signal circuit for a short to ground. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 33 |
| 26 | Test the cruise inhibit signal circuit for an open, a high resistance, or a short to voltage. Refer to Circuit Testing
andWiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 33 |
| 27 | Test the cruise engaged signal output circuit for an open or a high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 33 |
| 28 | Test the vehicle speed sensor signal circuit for an open or a high resistance between the cruise control module and PCM. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 35 |
| 29 | Inspect the brake ABS/TCC, cruise release switch for proper adjustment. Refer to Torque Converter Clutch/Cruise Control Release Switch Adjustment
in Automatic Transaxle - 4T65-E. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 31 |
| 30 | Inspect the stop lamp switch for proper adjustment. Refer to Stop Lamp Switch Adjustment
in Lighting Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 32 |
| 31 | Inspect for poor connections at the harness connector of the brake ABS/TCC, cruise release, switch. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 38 |
| 32 | Inspect for poor connections at the harness connector of the stop lamp switch. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 39 |
| 33 | Inspect for poor connections at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 40 |
| 34 | 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
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 41 |
| 35 | Inspect for poor connections at the harness connector of the cruise control module. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 43 | Go to Step 42 |
| 36 | Repair the ignition positive voltage circuit of the cruise control module. Refer to Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 43 | - |
| 37 | Repair the ground circuit of the cruise control module. Refer to Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 43 | - |
| 38 | Replace the brake ABS/TCC, cruise release switch. Refer to Torque Converter Clutch/Cruise Control Release Switch Replacement
in Automatic Transaxle - 4T65-E. Did you complete the replacement? |
- | Go to Step 43 | - |
| 39 | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement
in Lighting Systems. Did you complete the replacement? |
- | Go to Step 43 | - |
| 40 | Replace the PCM. Refer to Control Module References
in Computer/integrating Systems for replacement, setup, and programming. Did you complete the replacement? |
- | Go to Step 43 | - |
| 41 | Replace the cruise control switch. Refer to Multifunction, Turn Signal Switch Replacement
in Steering Wheel and Column. Did you complete the replacement? |
- | Go to Step 43 | - |
| 42 | Replace the cruise control module. Refer to Control Module References
in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? |
- | Go to Step 43 | - |
| 43 | Operate the vehicle within the conditions for cruise control operation. Does the cruise control system operate correctly? |
- | System OK | Go to Step 2 |