Diagnostic Aids
WARNING: This page is about a different car, the 2006 Buick LaCrosse and 2006 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Refer to SIR Caution
in Cautions and Notices.
Disable the inflatable restraint steering wheel module when performing this diagnostic table. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Perform the following in order to avoid a misdiagnosis:
- Ensure that the following cruise control switches are not stuck in the engaged position:
- On/off switch
- Set/coast switch
- Resume/accel switch
- With a scan tool, observe the cruise control function switch parameters, in the powertrain control module (PCM) cruise control data list, while rotating the steering wheel to both steering stops and individually activating each cruise control function switch separately. This will help eliminate the possibility of an internally shorted inflatable restraint steering wheel module coil.
- Inspect for proper operation of the stop lamps. Refer to Exterior Lighting Systems Description and Operation in Lighting Systems.
- For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Cruise Control Inoperative/Malfunctioning (3.6L)
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Cruise Control Schematics Connector End View Reference: Engine Controls Connector End Views in Engine Controls - 3.6L (LY7) |
||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Is DTC P0573 current in the engine control module (ECM)? | - | Go to DTC P0573 in Lighting Systems | Go to Step 3 |
| 3 |
|
- | Go to Step 4 | Go to Step 7 |
| 4 |
|
- | Go to Step 5 | Go to Step 8 |
| 5 |
|
- | Go to Step 6 | Go to Step 9 |
| 6 |
|
- | Go to Diagnostic Aids | Go to Step 9 |
| 7 |
|
- | Go to Step 14 | Go to Step 11 |
| 8 |
|
- | Go to Step 10 | Go to Step 20 |
| 9 |
IMPORTANT:
The cruise control on/off switch must be turned ON in order to correctly view the set/coast and the resume/accel switch resistance values with the DMM.
|
Off = O.L. On = 7.8 K Ω-8.6 K Ω Resume = 2.7 K Ω-3.0 K Ω Set = 1.2 K Ω-1.3 K Ω |
Go to Step 12 | Go to Step 18 |
| 10 |
IMPORTANT:
The cruise control on/off switch must be turned ON in order to correctly view the set/coast and the resume/accel switch resistance values with the DMM.
|
Off = O.L. On = 7.8 K Ω-8.6 K Ω Resume = 2.7 K Ω-3.0 K Ω Set = 1.2 K Ω-1.3 K Ω |
Go to Step 12 | Go to Step 13 |
| 11 | Test the cruise control set/coast and resume/accelerate 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 23 | Go to Step 19 |
| 12 | Test the cruise control set/coast and resume/accelerate switch signal circuit for the following:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 19 |
| 13 | Test the ignition 1 voltage circuit for the following, between C277 and the cruise control switch assembly.
Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 16 |
| 14 | Test the cruise control on switch signal circuit for a short to voltage. Refer to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 15 |
| 15 | Test the cruise control set/coast and resume/accelerate switch signal circuit for a short to voltage between C277 and the cruise control switch assembly. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 18 |
| 16 | Test the cruise control set/coast and resume/accelerate switch signal circuit for the following, between C277 and the cruise control switch assembly.
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 17 |
| 17 | Test the cruise control on switch signal circuit for the following:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 23 | Go to Step 18 |
| 18 | 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 23 | Go to Step 21 |
| 19 | Inspect for poor connections at the harness connector of the engine control module (ECM). 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 23 | Go to Step 22 |
| 20 | Repair the following in the ignition 1 voltage circuit.
Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? |
- | Go to Step 23 | - |
| 21 | Replace the cruise control switch. Refer to Steering Wheel Control Switch Assembly Replacement
in Steering Wheel and Column. Did you complete the replacement? |
- | Go to Step 23 | - |
| 22 | Replace the ECM. Refer to Control Module References
in Computer/Integrating Systems for replacement, setup and programming. Did you complete the replacement? |
- | Go to Step 23 | - |
| 23 |
|
- | System OK | Go to Step 2 |