GM Service Manual Online
For 1990-2009 cars only

Circuit Description

This DTC checks for an abnormal VSS input to the cruise control module or a malfunction within the cruise control module.

Diagnostic Aids

Check for the following:

    • DTCs in the powertrain control module
    • If the speedometer operates normally, the VSS is OK
    • Open or high resistance in the PPL/WHT wire between junction block 3 and the cruise control module
    • Faulty cruise control module

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation. Inspect the following harness connectors for backed out terminals, improper mating, broken lock, improperly formed or damaged terminals or for poor terminal-to-wire connection before replacing the suspect component:

    • Cruise control module connector
    • Junction block 3 C1
    • C210

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests the resistance of the cruise control servo magnetic clutch circuit.

Step

Action

Value(s)

Yes

No

Schematic Reference: Cruise Control Schematics

1

Did you perform the Diagnostic System Check - Cruise Control ?

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Go to Step 2

Go to Diagnostic System Check - Cruise Control

2

  1. Raise and suitably support the vehicle.
  2. Disconnect the cruise control module connector.
  3. Turn the ignition switch to the on position.
  4. Measure the voltage from cavity 12 while slowly rotating the front drive wheel with the transaxle in gear.

Does the reading vary within the specified range?

0-8 V

Go to Step 3

Go to Step 4

3

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 6

Go to Step 5

4

Repair the open or high resistance in the PPL/WHT wire between the module and junction block 3. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 6

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5

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

Is the repair complete?

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Go to Step 6

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6

  1. Turn OFF the ignition.
  2. Remove the STOP fuse.
  3. Remove the ECU-B fuse.
  4. Wait 30 seconds.
  5. Reinstall STOP and ECU-B fuses.
  6. Turn ON the ignition, with the engine OFF.
  7. Using the jumper, connect the DLC terminals Tc and E1.

Does the CRUISE indicator lamp flash the same trouble code?

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Go to Step 2

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