GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Cruise Resume/Accel switch is an input to the throttle actuator control (TAC) Module. This cruise control information is supplied to the PCM via serial data . This allows the PCM and TAC module to control and hold a requested speed. The Cruise Resume/Accel switch sends an ignition positive voltage signal to the TAC module when the switch is applied. This DTC sets if the TAC module senses a voltage on the Resume/ Accelerate switch signal circuit when voltage is not expected

Conditions for Running the DTC

The cruise control switch is ON.

Conditions for Setting the DTC

The TAC module detects the Resume/Accel switch is ON for longer than 90 seconds.

Action Taken When the DTC Sets

    • The PCM stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.
    • The cruise is disabled.

Conditions for Clearing the MIL/DTC

    • A last test failed, or the current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC clears after 40 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic.
    • Use a scan tool in order to clear the MIL/DTC.

Diagnostic Aids

Important: 

   • Remove any debris from the TAC module connector surfaces before servicing the TAC module. Inspect the TAC module connector gaskets when diagnosing/replacing the module. Ensure that the gaskets are installed correctly.
   • For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616 . Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.

    • Inspect for a resume/accel switch stuck in the engage position or the signal circuit is shorted to voltage.
    • For an intermittent, refer to Testing for Intermittent Conditions and Poor Connections .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if condition is present.

  2. This step determines if the switch is at fault.

  3. This steps determines if the circuit is shorted to a voltage.

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

1

Did you perform A Diagnostic System Check - Cruise Control?

Go to Step 2

Go to Diagnostic System Check - Cruise Control

2

    Important: If DTC P1518 is also set, diagnose P1518 first.

  1. Install the scan tool.
  2. Turn ON the ignition leaving the engine OFF.
  3. Turn OFF the cruise control switch.

Does the scan tool parameter indicate that the Cruise Resume/Accel switch is ON?

Go to Step  3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the appropriate TAC module harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Monitor the cruise control Resume/Accelerate switch parameter in the PCM data list.

Does the scan tool indicate that the cruise control Resume/ Accelerate switch is ON?

Go to Step   6

Go to Step  4

4

Test the cruise control 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   9

Go to Step 5

5

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  8

Go to Step  7

6

Inspect for poor connections at the harness connector of the TAC 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  9

Go to Step  8

7

Replace the cruise control switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Did you complete the replacement?

Go to Step  9

--

8

Replace the TAC module. Refer to Electronic Throttle Actuator Control Module Replacement in Engine Repair.

Did you complete the replacement?

Go to Step  9

--

9

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step  2

System OK