GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: This table diagnoses either the cruise control indicator lamp or the CRUISE indicator are always ON and that the cruise control system operates normally.

1

Did you review the Cruise Control System Description and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Cruise Control

2

Verify that the cruise control system is operational and that the cruise control indicator lamp or the CRUISE indicator are always ON.

Do the cruise control indicator lamps operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Turn the ignition to the OFF position.

Does the cruise control indicator lamp and the CRUISE indicator illuminate?

Go to Step 13

Go to Step 4

4

Turn the ignition ON with the engine OFF.

Does the CRUISE indicator located in the instrument cluster illuminate?

Go to Step 8

Go to Step 5

5

Does the cruise control indicator lamp located in the main cruise control switch illuminate?

Go to Step 6

Go to Step 2

6

Turn the ignition to OFF.

Disconnect the cruise control servo connector.

Turn the ignition ON with the engine OFF.

Does the cruise control indicator lamp illuminate?

Go to Step 7

Go to Step 15

7

With the cruise control servo connector still disconnected:

  1. Disconnect the main cruise control switch. Refer to Cruise Control Switch Replacement for access.
  2. Test for a short to ground between cavity 10 of the cruise control servo connector and ground.

Did you test a short to ground condition in the LT.GRN/WHT wire?

Go to Step 10

Go to Step 14

8

  1. Turn the ignition to OFF.
  2. Disconnect the cruise control servo connector.
  3. Turn the ignition ON with the engine OFF.

Does the CRUISE indicator lamp illuminate?

Go to Step 9

Go to Step 15

9

With the cruise control servo connector still disconnected:

  1. Disconnect instrument cluster connector C1. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console for access.
  2. Test for a short to ground between cavity 4 of the cruise control servo connector and ground.

Did you test a short to ground condition in the GRY/YEL wire?

Go to Step 11

Go to Step 12

10

Repair the short to ground in the LT.GRN/WHT wire between cavity 1 of the main cruise control switch connector and cavity 10 of the cruise control servo connector. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

11

Repair the short to ground in the GRY/YEL wire between instrument cluster connector C1 cavity 16 and cavity 4 of the cruise control servo connector. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

12

Repair or replace the instrument cluster printed circuit. Refer to Printed Instrument Cluster Circuit Replacement in Instrument Panel, Gauges and Console.

Did you complete the repair or replacement?

Go to Step 16

--

13

Repair the short to B+ in the positive voltage supply circuit to the cruise control indicator lamp or the CRUISE indicator. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

14

Replace the main cruise control switch. Refer to Cruise Control Switch Replacement .

Did you complete the replacement?

Go to Step 16

--

15

Replace the cruise control servo. Refer to Cruise Control Servo Replacement .

Did you complete the replacement?

Go to Step 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3