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For 1990-2009 cars only
Makes 🢒 Generic 🢒 1999 🢒 Unit Repair 🢒 Body and Accessories 🢒 Cruise Control 🢒 Cruise Control Inoperative

Cruise Control Inoperative w/o Inhibit

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. (Note to author: The proper switch name e.g. BRAKE, CRUISE RELEASE or CLUTCH switch [in the case of a manual transmission], must be used in the chart.

  2. (Note to author: The cruise engaged circuit from the PCM/VCM to terminal J of the cruise module, may not be used in all applications. This step as well as step 23 must be eliminated).

Step

Action

Yes

No

1

Did you perform the Cruise Control Diagnostic System Check?

Go to Step 2

Go to (LINK)

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/clutch 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 brake switch 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 Circuit Testing and 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 Circuit Testing and 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 Circuit Testing and 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 Circuit Testing and 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 Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 30

19

Test the brake/clutch circuit for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 39

Go to Step 25

20

Test the brake/clutch switch 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 39

Go to Step 25

21

Test the brake switch 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 39

Go to Step 26

22

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

Did you find and correct the condition?

Go to Step 39

Go to Step 29

25

Inspect the brake/clutch [cruise release] 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/clutch switch. Refer to Testing for Intermittent 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 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 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 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 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 (LINK) in Wiring Systems.

Did you complete the repair?

Go to Step 39

--

33

Repair the ground circuit of the cruise control module. Refer to (LINK) in Wiring Systems.

Did you complete the repair?

Go to Step 39

--

34

Replace the brake/clutch switch. Refer to (LINK) .

Did you complete the replacement?

Go to Step 39

--

35

Replace the brake switch. Refer to (LINK) .

Did you complete the replacement?

Go to Step 39

--

36

Replace the PCM. Refer to (LINK) in Engine Controls.

Did you complete the replacement?

Go to Step 39

--

37

Replace the cruise control switch. Refer to (LINK) .

Did you complete the replacement?

Go to Step 39

--

38

Replace the cruise control module. Refer to (LINK) .

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

Cruise Control Inoperative w/inhibit

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. (Note to author: The proper switch name BRAKE/CLUTCH or CRUISE RELEASE switch [in the case of a manual transmission], must be used in the chart. In the event a CANCEL or CLEAR switch is used, it is placed in this circuit and BRAKE/CANCEL or CLEAR switch would be used in the appropiate place).

  2. (Note to author: Use the proper scan tool name in this statement).

  3. (Note to author: When testing for an open, high resistance or short to B+ in the BRAKE/CANCEL or CLEAR switch circuit, a test of the Cruise Control Switch needs to be done).

  4. (Note to author: When testing for an open, high resistance or short to B+ in the BRAKE/CANCEL or CLEAR switch circuit, a test of the Cruise Control Switch needs to be done).

Step

Action

Yes

No

1

Did you perform the Cruise Control Diagnostic System Check?

Go to Step 2

Go to (LINK)

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 36

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 37

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 16

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 17

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 19

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 20

8

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

Does the test lamp illuminate?

Go to Step 9

Go to Step 21

9

Depress the brake pedal while monitoring the test lamp.

Does the test lamp illuminate?

Go to Step 22

Go to Step 10

10

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

Does the test lamp illuminate?

Go to Step 23

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 24

12

Probe the cruise disable/enable circuit with a test lamp that is connected to B+.

Does the test lamp illuminate?

Go to Step 25

Go to Step 13

13

Use a scan tool in order to command the cruise inhibit/enable OFF.

Does the test lamp illuminate?

Go to Step 14

Go to Step 26

14

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 15

Go to Step 27

15
  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 34

Go to Step 28

16

Test the circuit that illuminated the test lamp 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 43

Go to Step 34

17

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

Did you find and correct the condition?

Go to Step 43

Go to Step 18

18

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

Did you find and correct the condition?

Go to Step 43

Go to Step 34

19

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

Did you find and correct the condition?

Go to Step 43

Go to Step 34

20

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

Did you find and correct the condition?

Go to Step 43

Go to Step 34

21

Test the brake/clutch circuit for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 29

22

Test the brake/clutch switch 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 43

Go to Step 29

23

Test the brake switch 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 43

Go to Step 30

24

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

Did you find and correct the condition?

Go to Step 43

Go to Step 30

25

Test the cruise disable/enable circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 33

26

Test the cruise disable/enable circuit for an open, a high resistance, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 33

27

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

Did you find and correct the condition?

Go to Step 43

Go to Step 33

28

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

Did you find and correct the condition?

Go to Step 43

Go to Step 33

29

Inspect the brake/clutch [cruise release] switch for proper adjustment.

Did you find and correct the condition?

Go to Step 43

Go to Step 31

30

Inspect the brake switch for proper adjustment.

Did you find and correct the condition?

Go to Step 43

Go to Step 32

31

Inspect for poor connections at the harness connector of the brake/clutch switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 41

32

Inspect for poor connections at the harness connector of the brake switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 39

33

Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 40

34

Inspect for poor connections at the harness connector of the cruise control switch. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 41

35

Inspect for poor connections at the harness connector of the cruise control module. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 43

Go to Step 42

36

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 43

--

37

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

Did you complete the repair?

Go to Step 43

--

38

Replace the brake/clutch switch. Refer to (LINK).

Did you complete the replacement?

Go to Step 43

--

39

Replace the brake switch. Refer to (LINK).

Did you complete the replacement?

Go to Step 43

--

40

Replace the PCM. Refer to (LINK) in Engine Controls.

Did you complete the replacement?

Go to Step 43

--

41

Replace the cruise control switch. Refer to (LINK).

Did you complete the replacement?

Go to Step 43

--

42

Replace the cruise control module. Refer to (LINK).

Did you complete the replacement?

Go to Step 43

--

43

Operate the vehicle within the conditions for cruise control operation.

Does the cruise control system operate correctly?

System OK

Go to Step 2