GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Chevy C Pickup - 2WD 🢒 Body and Accessories 🢒 Cruise Control 🢒 Cruise Control Inoperative

Cruise Control Inoperative Diesel Engine

Step

Action

Value(s)

Yes

No

1

Did you perform the Cruise Control System Check?

--

Go to Step 2

Go to Cruise Control System Check

2
  1. Verify that no diagnostic trouble codes (DTCs) are set that could impact cruise control operations.
  2. Place the ignition switch to the RUN position.
  3. Disconnect the connector C2 at the powertrain control module (PCM).
  4. Connect a DMM, set on volts, between the PCM connector C2 cavity A11 for the CKT 397 (GRY) and ground.
  5. Place the cruise control switch in the ON position.

Is there battery voltage?

--

Go to Step 5

Go to Step 3

3
  1. Disconnect connector C266 at the steering column.
  2. Connect a DMM, set on volts, between connector C266 pin A13 for the CKT 41 (BRN) and ground.

Is there battery voltage?

--

Go to Step 4

Go to Step 18

4

Connect a J 39200 , set on ohms, between connector C266 cavities A 13 for the CKT 41 (BRN) pigtail wire and A 12 for the CKT 397 (GRY) pigtail wire.

Is there continuity?

--

Go to Step 19

Go to Step 20

5
  1. Connect a DMM, set on volts, between the PCM connector C2 cavity B11 for the CKT 84 (DK BLU) wire and ground.
  2. Actuate the S/C switch on the cruise control switch.

Is there battery voltage?

--

Go to Step 7

Go to Step 6

6
  1. Disconnect connector C266 at the steering column.
  2. Connect a DMM, set on ohms, between the connector C266 cavity A 13 for CKT 41 (BRN) pigtail wire and cavity A 14 for the CKT 84 (DK BLU) pigtail wire.
  3. Actuate the S/C switch on the cruise control switch.

Is there continuity?

--

Go to Step 21

Go to Step 22

7

Connect a DMM, set on volts, between the PCM connector C2 cavity B10 for the CKT 17 (WHT) wire and ground.

Is there battery voltage?

--

Go to Step 8

Go to Step 9

8
  1. Disconnect the connector at the stoplamp switch.
  2. Connect a DMM, set on ohms, between the stoplamp switch pins A and B.

Is there continuity?

--

Go to Step 23

Go to Step 24

9

With the DMM still connected, depress the brake pedal.

Is there battery voltage?

--

Go to Step 12

Go to Step 10

10
  1. Disconnect the connector at the stoplamp switch.
  2. Connect a DMM between the stoplamp switch connector cavity B for the CKT 140 (ORN) and ground.

Is there battery voltage?

--

Go to Step 11

Go to Step 25

11
  1. Connect a DMM, set on ohms, between the stoplamp switch pins A and B.
  2. Depress the brake pedal.

Is there continuity?

--

Go to Step 26

Go to Step 34

12

Connect a DMM, set on volts, between the PCM connector C2 cavity B9 for CKT 420 (PPL) and ground.

Is there battery voltage?

--

Go to Step 27

Go to Step 13

13
  1. Disconnect the connector at the stoplamp switch.
  2. Connect a DMM, set on volts, between the stoplamp switch connector cavity F for the CKT 441 (BRN) wire and ground.

Is there battery voltage?

--

Go to Step 14

Go to Step 28

14

Is the vehicle equipped with an automatic transmission?

--

Go to Step 15

Go to Step 16

15
  1. Use a DMM, set on Ohms, in order to backprobe the stoplamp switch pins E and F.
  2. Observe the DMM.
  3. Depress the brake pedal.
  4. Observe the DMM.

Is there continuity with the brake pedal released and no continuity with the brake pedal depressed?

--

Go to Step 30

Go to Step 29

16

Connect a DMM, set on volts, from CKT 420 (PPL) wire at the clutch pedal switch cavity B to ground.

Is there battery voltage?

--

Go to Step 17

Go to Step 31

17

Connect a DMM, set on volts, between the CKT 379 (BRN/WHT) at the clutch pedal position switch to ground.

Is there battery voltage?

--

Go to Step 32

Go to Step 33

18

Repair the open in CKT 41 (BRN) between the IP fuse block and connector C266. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

19

Repair the open in the CKT 397 (GRY) wire between the connector C266 and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

20
  1. Inspect for an open in CKT 41 (BRN) pigtail wire or in CKT 397 (GRY) pigtail wire in the steering column, repair as necessary. Refer to Wiring Repairs in Wiring Systems.
  2. If no opens are found, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt or Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Standard.

Is the repair complete?

--

Go to Cruise Control System Check

--

21

Repair the open in CKT 84 (DK BLU) between connector C266 and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

22
  1. Inspect for an open in CKT 84 (DK BLU) pigtail wire in the steering column, repair as necessary. Refer to Wiring Repairs in Wiring Systems.
  2. If no opens are found, replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt or Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Standard.

Is the repair complete?

--

Go to Cruise Control System Check

--

23

Adjust or replace the stoplamp switch.

The stoplamp switch contact is supposed to be open. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Is the repair complete?

--

Go to Cruise Control System Check

--

24

Repair the short to voltage in CKT 17 (WHT) between the stoplamp switch and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

25

Repair the open in CKT 140 (ORN) between the IP fuse block and the stoplamp switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

26

Repair the open in CKT 17 (WHT) between the stoplamp switch and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

27

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls -- 6.5L.

Is the repair complete?

--

Go to Cruise Control System Check

--

28

Repair the open in CKT 441 (BRN) between the IP fuse block and the stoplamp switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

29

Adjust or replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Is the repair complete?

--

Go to Cruise Control System Check

--

30

Repair the open in CKT 420 (PPL) between the stoplamp switch and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

31

Repair the open in the CKT 420 (PPL) between the stoplamp switch and the clutch pedal position switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

32

Repair the open in CKT 379 (BRN/WHT) between the clutch pedal position switch and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Cruise Control System Check

--

33

Replace the clutch pedal position switch. Refer to Clutch Pedal Engine Start Switch Replacement in Clutch.

Is the repair complete?

--

Go to Cruise Control System Check

--

34

Adjust or replace the stoplamp switch. The stoplamp switch contact should be closed with the brake pedal actuated. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Is the repair complete?

--

Go to Cruise Control System Check

--

Cruise Control Inoperative Gasoline Engines

Step

Action

Yes

No

Alternative Diagnosis

The J 42958 may be used if desired. Refer to Service Bulletin 83-90-08A.

1

Did you perform the Cruise Control System Check?

Go to Step 2

Go to Cruise Control System Check

2
  1. Turn OFF the ignition.
  2. Disconnect the cruise control module.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the ignition positive voltage circuit of the cruise control module with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 3

Go to Step 32

3

Probe the ignition positive voltage circuit of the cruise control module with a test lamp that is connected to the ground circuit of the cruise control module.

Does the test lamp illuminate?

Go to Step 4

Go to Step 33

4
  1. Turn ON the ignition, with the engine OFF.
  2. Turn OFF the cruise control.
  3. Probe the on/off, the set/coast, and the resume/accelerate circuits with a test lamp that is connected to a good ground.

Does the test lamp illuminate on any of the circuits?

Go to Step 14

Go to Step 5

5
  1. Turn ON the ignition, with the engine OFF.
  2. Turn ON the cruise control.
  3. Probe the on/off circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 15

6
  1. Probe the set/coast circuit with a test lamp that is connected to a good ground.
  2. Press and hold the SET/COAST switch.

Does the test lamp illuminate?

Go to Step 7

Go to Step 17

7
  1. Probe the resume/accelerate circuit with a test lamp that is connected to a good ground.
  2. Press and hold the RESUME/ACCEL switch.

Does the test lamp illuminate?

Go to Step 8

Go to Step 18

8

Probe the brake circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 19

9

Depress the brake pedal while monitoring the test lamp.

Does the test lamp illuminate?

Go to Step 20

Go to Step 10

10

Probe the cruise release circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 21

Go to Step 11

11

Depress the brake pedal while monitoring the test lamp.

Does the test lamp illuminate?

Go to Step 12

Go to Step 22

12

Probe the cruise engaged output circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 13

Go to Step 23

13
  1. Raise and suitably support the vehicle.
  2. Probe the VSS signal circuit with a DMM that is connected to a good ground.
  3. Set the DMM to the AC scale.
  4. Rotate one of the drive wheels.
  5. Observe the DMM.

Does the voltage displayed on the scan tool vary?

Go to Step 31

Go to Step 24

14

Test the circuit that illuminated the test lamp for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 30

15

Test the on/off circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 16

16

Test the ignition positive voltage circuit for an open or high resistance between the cruise control module and the cruise control switch. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 30

17

Test the set/coast circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 30

18

Test the resume/accelerate circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 30

19

Test the brake circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 25

20

Test the brake switch circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 25

21

Test the cruise release circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 26

22

Test the brake switch circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 26

23

Test the cruise engaged output circuit for an open, a high resistance, or a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 29

24

Test the speed sensor circuit for an open or a high resistance. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 29

25

Inspect the brake switch for proper adjustment.

Did you find and correct the condition?

Go to Step 39

Go to Step 27

26

Inspect the brake switch for proper adjustment.

Did you find and correct the condition?

Go to Step 39

Go to Step 28

27

Inspect for poor connections at the harness connector of the brake 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 39

Go to Step 34

28

Inspect for poor connections at the harness connector of the brake 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 39

Go to Step 35

29

Inspect for poor connections at the harness connector of the PCM. 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 39

Go to Step 36

30

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 39

Go to Step 37

31

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 39

Go to Step 38

32

Repair the ignition positive voltage circuit of the cruise control module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 39

--

33

Repair the ground circuit of the cruise control module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 39

--

34

Replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Did you complete the replacement?

Go to Step 39

--

35

Replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Did you complete the replacement?

Go to Step 39

--

36

Replace the VCM. Refer to VCM Replacement/Programming in Engine Controls.

Did you complete the replacement?

Go to Step 39

--

37

Replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt or Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Standard.

Did you complete the replacement?

Go to Step 39

--

38

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

Did you complete the replacement?

Go to Step 39

--

39

Operate the vehicle within the conditions for cruise control operation.

Does the cruise control system operate correctly?

System OK

Go to Step 2