Except Police Package

CHECKING THE SPEED CONTROL OPERATION (EXCEPT POLICE PACKAGE)





For a complete wiring diagram, refer to the Wiring Information.

1. SPEED CONTROL VERIFICATION TEST

NOTE: Diagnose and repair any Stop Lamp Switch, Speed Control, or communication DTCs between the Steering Control Module (SCM) and the Powertrain Control Module (PCM) before proceeding with this test.

NOTE: Check for any Technical Service Bulletins (TSBs) that pertain to the Speed Control System before proceeding with this test.

1. Road test the vehicle at a speed above 60 km/h (35 MPH).
2. Turn the speed control ON/OFF switch on.
3. Depress and release the SET switch. The speed control should engage.
4. Press and release the RESUME/ACCEL switch. The vehicle speed should increase by 3 km/h (2 MPH).
5. Using caution, depress and release the brake pedal. The speed control should disengage.
6. With the vehicle speed at least 60 km/h (35 MPH), press the RESUME/ACCEL switch. The speed control should resume at the previously set speed.
7. Hold down the COAST switch. The vehicle should decelerate.
8. While still holding down the COAST switch, ensure the vehicle speed is at least 60 km/h (35 MPH) and release the COAST switch. The vehicle should adjust and set a new vehicle speed.
9. With the speed control engaged, depress the ON/OFF switch. The speed control should disengage.

Does the speed control system operate properly?

Yes

- Test complete. The speed control system is operating correctly at this time.
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test

No

- Go To 2

2. STOP LAMP SWITCH
1. Road test the vehicle at a speed above 60 km/h (35 MPH).
2. Turn the speed control ON/OFF switch on.
3. Depress and release the SET switch. The speed control should engage.
4. Using caution, lightly depress and release the brake pedal. The speed control should disengage.

Does the Speed Control disengage when the brake pedal is applied?

Yes

- Go To 3

No

- The Stop Lamp Switch is adjusted incorrectly. Adjust the Stop Lamp Switch.
- Perform the appropriate verification test.

3. SPEED CONTROL SWITCH - S/C SIGNAL 1
1. Turn the ignition off.
2. Remove the Speed Control Switch.
3. Measure the resistance between the (V71) S/C Signal 1 terminal and the (V937) S/C Switch Ground terminal at the Speed Control Switch.
4. Monitor the Ohmmeter while cycling the Switch through each position.
5. The following resistance specs are taken between the (V71) S/C Signal 1 terminal and the (V937) S/C Switch Ground terminal at the Switch when holding the Switch in the following position:
- No function selected - 20.5k Ohms (±1k Ohms)
- On/Off - 464.6 Ohms (±50 Ohms)
- Set/Coast - 4.33k Ohms (±.5k Ohms)
- Cancel - 1.172k Ohms (±.2k Ohms)
- Resume/Accel - 8.81k Ohms (±.5k Ohms)

Does each function of the Speed Control Switch have the correct resistance value?

Yes

- Go To 4

No

- Replace the Speed Control Switch.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

4. SPEED CONTROL SWITCH - S/C SIGNAL 2
1. Measure the resistance between the (V72) S/C Signal 2 terminal and the (V937) S/C Switch Ground terminal at the Speed Control Switch.
2. Monitor the Ohmmeter while cycling the Switch through each position.
3. The following resistance specs are taken between the (V72) S/C Signal 2 terminal and the (V937) S/C Switch Ground terminal at the Switch when holding the Switch in the following position:
- No function selected - 20.5k Ohms (±1k Ohms)
- On/Off - 6.21 Ohms (±.5 Ohms)
- Set/Coast - 3.294k Ohms (±.5k Ohms)
- Cancel -.796k Ohms (±.1k Ohms)
- Resume/Accel - 1.715k Ohms (±.2k Ohms)

Does each function of the Speed Control Switch have the correct resistance value?

Yes

- Go To 5

No

- Replace the Speed Control Switch.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

5. (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO VOLTAGE




1. Disconnect the SCM C4 harness connector.
2. Turn the ignition on.
3. Measure the voltage on the (V71) S/C Signal 1 circuit in the S/C Switch harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (V71) S/C Signal 1 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

No

- Go To 6

6. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE




1. Measure the voltage on the (V72) S/C Signal 2 circuit in the S/C Switch harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (V72) S/C Signal 2 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

No

- Go To 7

7. (V71) S/C SIGNAL 1 CIRCUIT OPEN OR EXCESSIVE RESISTANCE




1. Turn the ignition off.
2. Measure the resistance of the (V71) S/C Signal 1 circuit from the Speed Control Switch harness connector and the SCM C4 harness connector.

Is the resistance below 5.0 Ohms for each measurement?

Yes

- Go To 8

No

- Repair the open or excessive resistance in the (V71) S/C Signal 1 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

8. (V72) S/C SIGNAL 2 CIRCUIT OPEN OR EXCESSIVE RESISTANCE




1. Measure the resistance of the (V72) S/C Signal 2 circuit from the Speed Control Switch harness connector and the SCM C4 harness connector.

Is the resistance below 5.0 Ohms for each measurement?

Yes

- Go To 9

No

- Repair the open or excessive resistance in the (V72) S/C Signal 2 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

9. (V937) S/C SWITCH GROUND CIRCUIT OPEN OR EXCESSIVE RESISTANCE




1. Measure the resistance of the (V937) S/C Switch Ground circuit from the Speed Control Switch harness connector and the SCM C4 harness connector.

Is the resistance below 5.0 Ohms for each measurement?

Yes

- Go To 10

No

- Repair the open or excessive resistance in the (V937) S/C Switch Ground circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

10. (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the (V71) S/C Signal 1 circuit in the S/C Switch harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the short to ground in the (V71) S/C Signal 1 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

No

- Go To 11

11. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the (V72) S/C Signal 2 circuit in the S/C Switch harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the short to ground in the (V72) S/C Signal 2 circuit.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

No

- Go To 12

12. STEERING CONTROL MODULE (SCM)
1. Connect the SCM C4 and Speed Control Switch harness connectors.
2. Turn the ignition on.
3. With a scan tool, monitor the SCM Cruise Control Switch Status and Cruise Control On/Off Button state.
4. Cycle the Speed Control Switch through each position: On/Off, Set/Coast, Cancel, and Resume/Accel.

NOTE: The Cruise Control Switch Status and Cruise Control On/Off Button state should match each of the actual selections being made with the Speed Control Switch.

Does the scan tool match each of the actual switch selection?

Yes

- Go To 13

No

- Replace and program the Steering Control Module (SCM).
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

13. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Steering Column Module (SCM) and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the SCM and PCM connectors.
4. Perform any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform the PCM VERIFICATION TEST. Powertrain Verification Test