GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important:

    • To avoid misdiagnosis:
    • Check throttle linkage for mechanical binding which could cause system to malfunction.
    • Check for stored Diagnostic Trouble Codes (DTCs) in the PCM. Refer to Powertrain Control Module Diagnosis in Engine Controls 3.8L or Powertrain Control Module Diagnosis in Engine Controls 3.5L.
      • The PCM will inhibit cruise control:
      • When vehicle speed is less than 40 km/h (25 mph).
      • When PARK, REVERSE, NEUTRAL, or 1st gear is indicated by the transaxle range switch.
      • When an over/undercharged battery condition exists.
      • With low engine RPM.
      • With high engine RPM (fuel cut-off). Refer to Powertrain Control Module Description in Engine Controls 3.8L or Powertrain Control Module Description in Engine Controls 3.5L for more information.
      • Verify all connectors while testing.

1

Was the Cruise Control System Check performed?

--

Go to Step 2

Go to Cruise Control System Check

2

  1. Connect the J 42958 as specified in the user manual.
  2. Turn Ignition to the on position.
  3. Place cruise switch in the off position.

Are the Brake and Ignition lamps illuminated on the J 42958?

--

Go to Step 4

Go to Step 3

3

Check the Cruise fuse for an open.

Is the Cruise fuse open?

--

Go to Step 18

Go to Step 10

4

Set the Cruise Switch to the on position.

Do the On/Off, Brake, and Cruise lamps illuminate on the J 42958?

--

Go to Step 5

Go to Step 11

5

Press and hold the Set/Coast switch.

Does the Set/Hold lamp illuminate on the J 42958?

--

Go to Step 6

Go to Step 13

6

Press and hold the Res/Acc switch.

Does the Res/Acc lamp illuminate on the J 42958?

--

Go to Step 7

Go to Step 14

7

Press and hold the Clear switch.

Does the Brake Switch lamp turn off on the J 42958?

--

Go to Step 8

Go to Step 15

8

Press and hold the Brake pedal.

Does the Brake Lights lamp illuminate and the Brake lamp turn off on the J 42958?

--

Go to Step 9

Go to Step 17

9

  1. Leaving the J 42958 connected road test the vehicle at a minimum of 10 MPH.
  2. Have an assistant observe the J 42958 VSS lamp.

Does the VSS lamp flash with speed?

--

Go to Step 30

Go to Powertrain On Board Diagnostic (OBD) System Check in Ene Controls 3.8L or

Powertrain On Board Diagnostic (OBD) System Check in Engine Controls 3.5L

10

  1. Disconnect the J 42958
  2. Reconnect the Cruise Control Module connector.
  3. Using a test light, backprobe between the Cruise control Module connector terminal F and ground.

Does the test light illuminate?

--

Go to Step 11

Go to Step 19

11

Using a test light, backprobe between the Cruise Control Switch connectror terminal D and ground.

Does the test light illuminate?

--

Go to Step 12

Go to Step 20

12

  1. Using a test light, backprobe between the Cruise Control Switch connector terminal A and ground.
  2. Press and hold the Cruise Control Switch in the ON position.

Does the test light illuminate?

--

Got to Step 21

Got to Step 27

13

  1. Using a test light, backprobe between the steering column connector (behind the airbag) terminal B and ground.
  2. Press and hold the set switch.

Does the test light illuminate?

--

Go to Step 22

Go to Step 30

14

  1. Using a test light, probe between the steering column connector (behind the airbag) terminal C and ground
  2. Press and hold the Res/Acc switch.

Does the test light illuminte?

--

Go to step 23

Go to Step 28

15

Using a test light, probe between the cruise control release switch terminal A and ground.

Does the test light illuminate?

--

Go to Step 25

Go to Step 16

16

Using a test light, probe between the cruise control release switch terminal B and ground.

Does the test light illuminate?

--

Go to Step 28

Go to Step 24

17

Press and hold the Brake Pedal.

Do the stop lamps illuminate?

--

Go to Step 26

Go to Automatic Transmission Shift Lock Control System Check

18

Repair the short in circuit 341.

Is the repair complete?

--

Go to Cruise Control System Check

--

19

Repair the open in circuit 341.

Is the repair complete?

--

Go to Cruise Control System Check

--

20

Repair the open in circuit 43.

Is the repair complete?

--

Go to Cruise Control System Check

--

21

Repair the open in circuit 397.

Is the repair complete?

--

Go to Cruise Control System Check

--

22

Repair the open in circuit 84.

Is the repair complete?

--

Go to Cruise Control System Check

--

23

Repair the open in circuit 87.

Is the repair complete?

--

Go to Cruise Control System Check

--

24

Repair the open in circuit 986.

Is the repair complete?

--

Go to Cruise Control System Check

--

25

Repair the open in circuit 86.

Is the repair complete?

--

Go to Cruise Control System Check

--

26

Repair the open in circuit 17.

Is the repair complete?

--

Go to Cruise Control System Check

--

27

Replace the Cruise Control Swtich. Refer to Cruise Control and Hazard Warning Switch Replacement in Instrument Panel, Gauges and Console for service procedure.

Is the repair complete?

--

Go to Cruise Control System Check

--

28

Replace the Cruise Control Release Swtich. Refer to Cruise Control Release Switch Replacement for service procedure.

Is the repair complete?

--

Go to Cruise Control System Check

--

29

Replace the RH Steering Wheel Control Switch. Refer to Steering Wheel Control Switches Replacement for service procedure.

Is the repair complete?

--

Go to Cruise Control System Check

--

30

  1. Check the Cruise Control Module connector for proper terminal contact. Repair any poor terminal contact found.
  2. If no poor terminal contact was found replace the Cruise Control Module. Refer to Cruise Control Module Replacement for service procedure.

Is the repair complete?

--

Go to Cruise Control System Check

--