GM Service Manual Online
For 1990-2009 cars only

Cruise Control Indicator Always On Without Throttle Actuator Control

Step

Action

Values

Yes

No

Schematic Reference: Cruise Control Schematics

Connector End View Reference: Cruise Control Connector End Views

1

Did you perform the Cruise Control Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Cruise Control

2

Turn the ignition ON, with the engine OFF.

Does the Cruise indicator illuminate after the instrument panel cluster (IPC) displays test?

--

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

  1. Turn the ignition OFF.
  2. Install a scan tool.
  3. Turn the ignition ON, with the engine OFF.
  4. With the scan tool, observe the Cruise Control parameter in the IPC data list.

Does the Cruise Lamp parameter display On?

--

Go to Step 4

Go to Step 9

4

  1. Turn the ignition OFF.
  2. Disconnect the cruise control module.
  3. Turn the ignition ON, with the engine OFF.
  4. With a DMM, measure the voltage of the cruise control engaged signal circuit.

Does the voltage measure at approximately the specified voltage?

B+

Go to Step 7

Go to Step 5

5

Test the Cruise control engaged signal circuit 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 10

Go to Step 6

6

Inspect for a poor connection 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 10

Go to Step 8

7

Replace the cruise control module. Refer to Cruise Control Module Replacement .

Did you complete the replacement?

--

Go to Step 10

--

8

Important: Program the replacement PCM.

Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls-4.3L

Did you complete the replacement?

--

Go to Step 10

--

9

Replace the Instrument Panel Cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Does the system operate properly?

--

System OK

Go to Step 2

Cruise Control Indicator Always On With Throttle Actuator Control

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

Connector End View Reference: Cruise Control Connector End Views

1

Did you perform the Cruise Control Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Cruise Control

2

Turn the ignition ON, with the engine OFF.

Does the Cruise indicator illuminate after the instrument panel cluster (IPC) displays test?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

  1. Turn the ignition OFF.
  2. Install a scan tool.
  3. Turn the ignition ON, with the engine OFF.
  4. With the scan tool, observe the Cruise Control parameter in the IPC data list.

Does the Cruise Lamp parameter display On?

Go to Step 4

Go to Step 5

4

Important: Program the replacement PCM.

Replace the PCM. Refer to the appropriate procedure:

    •  Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L, and 6.0L
    •  Engine Control Module Replacement in Engine Controls - 6.6L (LLY)
    •  Engine Control Module Replacement in Engine Controls - 6.6L (LB7)
    •  Powertrain Control Module Replacement in Engine Controls - 8.1L

Did you complete the replacement?

Go to Step 6

--

5

Replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

Go to Step 6

--

6

Operate the system in order to verify the repair.

Does the system operate properly?

System OK

Go to Step 2