Cruise Control Inoperative/Malfunctioning WO/ETC
Diagnostic Aids
Important: Perform the following in order to avoid misdiagnosis.
• Inspect for proper operation of brake lamps and clutch switch, if equipped. • Inspect for proper operation of the transmission range switch. • Inspect throttle linkage for mechanical binding which could cause the
system to malfunction. • Inspect cruise control cable adjustment, should have minimum slack. • EMI on the speed sensor signal circuit may cause erratic cruise control
operation.
Conditions for Enabling Cruise Control
The vehicle speed is greater than 40 km/h (25 mph).
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Cruise Control Schematics | ||||
1 | Did you perform the Cruise Control Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the test lamp illuminate? | -- | Go to Step 3 | Go to Step 33 |
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 34 |
4 |
Does the test lamp illuminate on any of the circuits? | -- | Go to Step 16 | Go to Step 5 |
5 |
Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 17 |
6 |
Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 19 |
7 |
Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 20 |
8 | Probe the TCC/brake, cruise release signal circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? | -- | Go to Step 11 | Go to Step 9 |
9 | Is the vehicle equipped with a manual transmission? | -- | Go to Step 10 | Go to Step 21 |
10 |
Does the test lamp illuminate? | -- | Go to Step 22 | Go to Step 21 |
11 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? | -- | Go to Step 23 | Go to Step 12 |
12 | Probe the stoplamp switch signal circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? | -- | Go to Step 24 | Go to Step 13 |
13 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? | -- | Go to Step 14 | Go to Step 25 |
14 | Probe the cruise engaged signal circuit with a DMM that is connected to a good ground. Does the voltage measure near the specified value? | B+ | Go to Step 15 | Go to Step 26 |
15 | Check the speedometer for proper operation. Does the speedometer operate properly? | -- | Go to Step 27 | Go to Symptoms - Instrument Panel, Gages and Console in Instrument Panel, Gages, and Console |
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 40 | Go to Step 30 |
17 | Test the cruise control on/off signal circuit for an open, high resistance or short to ground and the set/coast, resume/accel signal circuits 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 40 | Go to Step 18 |
18 | Test the ignition positive voltage circuit of the cruise control switch for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 40 | Go to Step 30 |
19 | Test the set/coast switch signal 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 40 | Go to Step 30 |
20 | Test the resume/accelerate switch signal 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 40 | Go to Step 30 |
21 | Test the TCC/ brake, cruise release signal 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 40 | Go to Step 28 |
22 | Test the TCC/ brake, cruise release signal circuit for an open or a high resistance between the CPP switch and the cruise control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 40 | Go to Step 35 |
23 | Test the TCC/ brake, cruise release switch signal 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 40 | Go to Step 28 |
24 | Test the stoplamp switch signal 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 40 | Go to Step 28 |
25 | Test the stoplamp switch signal 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 40 | Go to Step 28 |
26 | Test the cruise engaged signal circuit for an open, a high resistance, or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 40 | Go to Step 29 |
27 | Test the speed sensor circuit for an open or a high resistance between the PCM and cruise control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 40 | Go to Step 31 |
28 | Inspect for poor connections at the harness connector of the stop lamp 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 40 | Go to Step 36 |
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 40 | Go to Step 37 |
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 complete the replacement? | -- | Go to Step 40 | Go to Step 38 |
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 complete the replacement? | -- | Go to Step 40 | Go to Step 39 |
32 | Inspect for poor connections at the harness connector of the CPP switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 40 | Go to Step 35 |
33 | Repair the ignition positive voltage circuit of the cruise control module. Refer to Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 40 | -- |
34 | Repair the ground circuit of the cruise control module. Refer to Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 40 | -- |
35 | Replace the CPP switch. Refer to Clutch Pedal Engine Start Switch Replacement in Clutch. Did you complete the replacement? | -- | Go to Step 40 | -- |
36 | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Did you complete the replacement? | -- | Go to Step 40 | -- |
37 |
Important: The PCM must be reprogrammed after replacement. Refer to Powertrain Control Module Programming in Engine Controls - 4.3L, or Powertrain Control Module Programming in Engine Controls - 4.8L, 5.3L, 6.0L. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.3L, or Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L, 6.0L. Did you complete the replacement? | -- | Go to Step 40 | -- |
38 | Replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column. Did you complete the replacement? | -- | Go to Step 40 | -- |
39 | Replace the cruise control module. Refer to Cruise Control Module Replacement . Did you complete the replacement? | -- | Go to Step 40 | -- |
40 | 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/Malfunctioning W/ETC
Diagnostic Aids
Important: Perform the following in order to avoid misdiagnosis.
• Inspect for proper operation of brake lamps and clutch switch, if equipped. • Inspect for proper operation of the transmission range switch. • EMI on the speed sensor signal circuit may cause erratic cruise control
operation.
Conditions for Enabling Cruise Control
The vehicle speed is greater than 40 km/h (25 mph).
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Cruise Control Schematics | |||
1 | Did you perform A Diagnostic System Check - Cruise Control? | Go to Step 2 | |
2 |
Does the test lamp illuminate on any of the circuits? | Go to Step 16 | Go to Step 3 |
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 17 |
4 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 19 |
5 |
Does the test lamp illuminate? | Go to Step 6 | Go to Step 20 |
6 | Probe the stop lamp switch signal circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 23 | Go to Step 7 |
7 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? | Go to Step 8 | Go to Step 21 |
8 | Is the vehicle equipped with a manual transmission? | Go to Step 9 | Go to Step 11 |
9 |
Does the test lamp illuminate? | Go to Step 10 | Go to Step 14 |
10 | Press the clutch pedal while monitoring the test lamp. Does the test lamp illuminate? | Go to Step 27 | Go to Step 11 |
11 | Probe the brake switch signal circuit of the ECM harness connector with a test lamp connected to a good ground. Does the test lamp illuminate? | Go to Step 12 | Go to Step 15 |
12 | Press the brake pedal while monitoring the test lamp. Does the test lamp illuminate? | Go to Step 24 | Go to Step 13 |
13 | Check the speedometer for proper operation. Does the speedometer operate properly? | Go to Step 33 | Go to Symptoms - Instrument Panel, Gages and Console in Instrument Panel, Gages and Console |
14 |
Does the test lamp illuminate? | Go to Step 26 | Go to Step 28 |
15 |
Does the test lamp illuminate? | Go to Step 25 | Go to Step 29 |
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 38 | Go to Step 32 |
17 | Test the on/off signal circuit for a open, high resistance or short to ground and the S/C and R/A signal circuits 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 38 | Go to Step 18 |
18 | Test the ignition positive voltage circuit of the cruise control switch for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 32 |
19 | Test the set/coast circuit for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 32 |
20 | Test the resume/accelerate circuit for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 32 |
21 | Test the stop lamp signal circuit for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 22 |
22 | Test the stop lamp ignition positive voltage circuit for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 31 |
23 | Test the stop lamp switch signal 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 38 | Go to Step 31 |
24 | 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 38 | Go to Step 31 |
25 | Test the brake switch signal circuit of the PCM harness 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 38 | Go to Step 31 |
26 | Test the CPP signal circuit for a open, high resistance or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 38 | Go to Step 30 |
27 | Test the CPP signal circuit of the PCM harness 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 38 | Go to Step 30 |
28 | Repair the open in the ignition positive voltage circuit of the CPP switch. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 38 | -- |
29 | Repair the open in the ignition positive voltage circuit of the stop lamp switch. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 38 | -- |
30 | Inspect for poor connections at the harness connector of the CPP 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 38 | Go to Step 34 |
31 | Inspect for poor connections at the harness connector of the stop lamp 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 38 | Go to Step 35 |
32 | 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 38 | Go to Step 36 |
33 | Inspect for poor connections at the harness connector of the Throttle Actuator Control (TAC) 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 38 | Go to Step 37 |
34 | Replace the CPP switch. Refer to Clutch Pedal Engine Start Switch Replacement . Did you complete the replacement? | Go to Step 38 | -- |
35 | Replace the Stop lamp switch. Refer to Stop Lamp Switch Replacement . Did you complete the replacement? | Go to Step 38 | -- |
36 | Replace the cruise control switch. Refer to Turn Signal and Multifunction Switch Assembly - Assemble - Off Vehicle in Steering Wheel and Column. Did you complete the replacement? | Go to Step 38 | -- |
37 | Replace the Throttle Actuator Control (TAC) Module. Refer to Electronic Throttle Actuator Control Module Replacement in Engine Controls - 6.0L, or Electronic Throttle Actuator Control Module Replacement in Engine Controls - 8.1L. Did you complete the replacement? | Go to Step 38 | -- |
38 | 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/Malfunctioning Diesel
Diagnostic Aids
Important: Perform the following in order to avoid misdiagnosis.
• Inspect for proper operation of brake lamps and clutch switch, if equipped. • Inspect for proper operation of the transmission range switch. • EMI on the speed sensor signal circuit may cause erratic cruise control
operation. • Wiring on upfitted equipment must also be tested.
Conditions for Enabling Cruise Control
The vehicle speed is greater than 40 km/h (25 mph).
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Cruise Control Schematics | |||
1 | Did you perform A Diagnostic System Check - Cruise Control? | Go to Step 2 | |
2 |
Did the scan tool parameter change state? | Go to Step 3 | Go to Step 9 |
3 |
Did the cruise control Set/Coast parameter change state? | Go to Step 4 | Go to Step 14 |
4 |
Did the cruise control Resume Accelerate parameter change state? | Go to Step 5 | Go to Step 15 |
5 |
Did the stop lamp switch parameter change state? | Go to Step 6 | Go to Step 10 |
6 |
Did the cruise release switch parameter change state? | Go to Step 7 | Go to Step 11 |
7 | Is the vehicle equipped with a manual transmission? | Go to Step 8 | Go to Step 29 |
8 |
Did the CPP switch parameter change state? | Go to Step 29 | Go to Step 12 |
9 |
Did the test lamp illuminate? | Go to Step 13 | Go to Step 21 |
10 |
Did the test lamp illuminate? | Go to Step 16 | Go to Step 22 |
11 |
Did the test lamp illuminate? | Go to Step 18 | Go to Step 23 |
12 |
Did the test lamp illuminate? | Go to Step 20 | Go to Step 24 |
13 | Test the cruise control ON switch signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 28 |
14 | Test the cruise control Set/Coast signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 28 |
15 | Test the cruise control Resume/Accelerate signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 28 |
16 | Test the stop lamp switch signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 17 |
17 | Check the stop lamp switch for proper adjustment. Did you find and correct the condition? | Go to Step 35 | Go to Step 25 |
18 | Test the TCC/Brake switch signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 19 |
19 | Check the TCC/Brake switch for proper adjustment. Did you find and correct the condition? | Go to Step 35 | Go to Step 26 |
20 | Test the CPP switch signal circuit for a open, high resistance, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 35 | Go to Step 27 |
21 | Repair the open, high resistance or short to ground in the multifunction turn signal lever ignition positive voltage feed circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 35 | -- |
22 | Repair the open, high resistance or short to ground in the stop lamp switch battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 35 | -- |
23 | Repair the open, high resistance or short to ground in the TCC/Brake switch battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 35 | -- |
24 | Repair the open, high resistance or short to ground in the CPP switch battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 35 | -- |
25 | Inspect for poor connections at the harness connector of the stop lamp 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 35 | Go to Step 30 |
26 | Inspect for poor connections at the harness connector of the TCC/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 35 | Go to Step 31 |
27 | Inspect for poor connections at the harness connector of the CPP 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 35 | Go to Step 32 |
28 | Inspect for poor connections at the harness connector of the multifunction turn signal lever. 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 35 | Go to Step 33 |
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 35 | Go to Step 34 |
30 | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Did you complete the repair? | Go to Step 35 | -- |
31 | Replace the TCC/Brake switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Did you complete the repair? | Go to Step 35 | -- |
32 | Replace the CPP switch. Refer to Clutch Pedal Engine Start Switch Replacement in Clutch. Did you complete the repair? | Go to Step 35 | -- |
33 | Replace the multifunction turn signal lever. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column. Did you complete the repair? | Go to Step 35 | -- |
34 |
Important: The PCM must be reprogrammed after replacement. Refer to Engine Control Module Programming Procedure in Engine Controls - 6.6L. Replace the PCM. Refer to Engine Control Module Replacement in Engine Controls - 6.6L. | Go to Step 35 | -- |
35 | Operate the vehicle with in the conditions for cruise control operation. Does the cruise control system operate properly? | System OK | Go to Step 2 |
