Diagnostic Aids
WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Perform the following in order to avoid misdiagnosis.
- Inspect for proper operation of the brake lamps.
- Inspect for proper operation of the transmission range switch.
- Inspect throttle linkage for mechanical binding which could cause the system to malfunction.
Cruise Control Inoperative/Malfunctioning (3.4L)
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Cruise Control Schematics | ||||
| 1 | Did you perform the Cruise Control Diagnostic System Check? | - | Go to Step 2 | Go to Diagnostic System Check - Cruise Control (3.4L) or Diagnostic System Check - Cruise Control (3.6L) |
| 2 |
|
- | Go to Step 3 | Go to Step 29 |
| 3 | Connect the test lamp between the ignition positive voltage circuit and the ground circuit of the cruise control module. Does the test lamp illuminate? |
- | Go to Step 4 | Go to Step 30 |
| 4 |
|
- | Go to Step 13 | Go to Step 5 |
| 5 |
|
- | Go to Step 6 | Go to Step 14 |
| 6 |
|
- | Go to Step 7 | Go to Step 16 |
| 7 |
|
- | Go to Step 8 | Go to Step 17 |
| 8 | Connect the test lamp between the cruise control release signal circuit and a good ground. Does the test lamp illuminate? |
- | Go to Step 19 | Go to Step 18 |
| 9 | Connect the test lamp between the stop lamp signal circuit and a good ground. Does the test lamp illuminate? |
- | Go to Step 20 | Go to Step 10 |
| 10 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? |
- | Go to Step 11 | Go to Step 21 |
| 11 | Measure the voltage at the cruise control engaged signal circuit. Does the voltage measure near the specified value? |
B+ | Go to Step 12 | Go to Step 22 |
| 12 | Check the speedometer for proper operation. Does the speedometer operate properly? |
- | Go to Step 23 | Go to Speedometer and/or Odometer Inaccurate or Inoperative in Instrument Panel, Gages and Console |
| 13 | Test the suspected switch signal circuit for a short to voltage. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 27 |
| 14 | Test the cruise control on/off switch signal circuit for an open or for a high resistance. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 15 |
| 15 | Test the ignition positive voltage circuit of the cruise control on/off switch for an open or for a high resistance. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 27 |
| 16 | Test the cruise control set/coast switch signal circuit for an open or for a high resistance. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 27 |
| 17 | Test the cruise control resume/accelerate switch signal circuit for an open or for a high resistance. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 27 |
| 18 | Test the cruise control release switch signal circuit for an open or for a high resistance. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 24 |
| 19 | Test the cruise control release switch signal circuit for a short to voltage. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 9 |
| 20 | Test the stop lamp switch signal circuit for a short to voltage. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Stop Lamps Always On in Lighting Systems |
| 21 | Test the stop lamp switch signal circuit for an open or for a high resistance between the center console fuse block and the cruise control module. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Stop Lamps Inoperative in Lighting Systems |
| 22 | Test the cruise engaged signal circuit for an open, for a high resistance, or for a short to ground. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 26 |
| 23 | Test the vehicle speed signal circuit for an open or for a high resistance between the PCM and the cruise control module. Refer to Circuit Testing
and to Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 28 |
| 24 | Inspect the cruise control release switch for proper adjustment. Refer to Cruise Release Switch Adjustment . Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 25 |
| 25 | Inspect for poor connections at the harness connector of the cruise control release switch. Refer to Testing for Intermittent Conditions and Poor Connections
and to Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 31 |
| 26 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections
and to Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 32 |
| 27 | Inspect for poor connections at the harness connector of the cruise control switch. Refer to Testing for Intermittent Conditions and Poor Connections
and to Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 33 |
| 28 | Inspect for poor connections at the harness connector of the cruise control module. Refer to Testing for Intermittent Conditions and Poor Connections
and to Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 35 | Go to Step 34 |
| 29 | 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 35 | - |
| 30 | Repair the ground circuit of the cruise control module. Refer to Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 35 | - |
| 31 | Replace the cruise control release switch. Refer to Cruise Release Switch Replacement . Did you complete the replacement? |
- | Go to Step 35 | - |
| 32 |
IMPORTANT:
Program the replacement PCM. Refer to Service Programming System (SPS)
in Programming. Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement
in Engine Controls.Did you complete the replacement? |
- | Go to Step 35 | - |
| 33 | 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 35 | - |
| 34 | Replace the cruise control module. Refer to Cruise Control Module Replacement . Did you complete the replacement? |
- | Go to Step 35 | - |
| 35 |
|
- | System OK | Go to Step 2 |