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Pinpoint Test C: The Cruise Control Switches Do Not Operate Correctly




Cruise Control

Pinpoint Tests

Pinpoint Test C: The Cruise Control Switches Do Not Operate Correctly

Refer to Wiring Diagram Set 31, Cruise Control for schematic and connector information. Diagrams By Number

Normal Operation

Voltage is sent from the PCM to the cruise control switches. When a switch is pressed, the voltage is routed through a specific resistor value for each function and the PCM grounds the reference voltage. The PCM uses this reference voltage to determine which cruise control input function has been selected.

- DTC P0579:00 (Cruise Control Multifunction Input A Circuit Range/Performance: No Sub Type Information) - sets when a cruise control switch is stuck or the switch circuits are open, shorted to voltage or shorted to ground.
- DTC P0581:00 (Cruise Control Multifunction Circuit High: No Sub Type Information) - sets when the cruise control switch circuits are shorted to voltage or open.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Clockspring
- Cruise control switch(es)
- PCM



PINPOINT TEST C: THE CRUISE CONTROL SWITCHES DO NOT OPERATE CORRECTLY

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

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C1 CHECK THE CRUISE CONTROL SWITCH


- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Press each cruise control switch while monitoring the cruise control switch PID (SCCS).





- Does the PID value agree with the switch position?

Yes
GO to C7.

No
If only one switch does not display the correct PID value, INSTALL a new cruise control switch. REFER to Cruise Control Switch Service and Repair. TEST the system for normal operation.

Otherwise, GO to C2.

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C2 CHECK THE CRUISE CONTROL SWITCH CIRCUITRY FOR A SHORT TO VOLTAGE


- Ignition OFF.
- Disconnect: PCM C175b.
- Ignition ON.
- Measure the voltage between the PCM C175b-64, circuit 8-PG13 (WH), harness side and ground; and between the PCM C175b-48, circuit 9-PG13 (WH), harness side and ground.




- Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR the DTCs. TEST the system for normal operation.

No
GO to C3.

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C3 CHECK THE CRUISE CONTROL SWITCH CIRCUITRY FOR A SHORT TO GROUND


- Ignition OFF.
- Remove the driver air bag module. Refer to Restraint Systems.
- Disconnect: Upper Clockspring .
- Measure the resistance between the PCM C175b-64, circuit 8-PG13 (WH), harness side and ground; and between the PCM C175b-48, circuit 9-PG13 (WH), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to C5.

No
GO to C4.

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C4 CHECK THE CLOCKSPRING FOR A SHORT TO GROUND


- Disconnect: Clockspring C218.
- Measure the resistance between the PCM C175b-64, circuit 8-PG13 (WH), harness side and ground; and between the PCM C175b-48, circuit 9-PG13 (WH), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
INSTALL a new clockspring. INSTALL the driver air bag module. REFER to Restraint Systems. CLEAR the DTCs. TEST the system for normal operation.

No
REPAIR the circuit in question. INSTALL the driver air bag module. REFER to Restraint Systems. CLEAR the DTCs. TEST the system for normal operation.

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C5 CHECK THE CRUISE CONTROL SWITCH CIRCUITRY FOR AN OPEN


- Disconnect: Clockspring C218.
- Measure the resistance between the PCM C175b-64, circuit 8-PG13 (WH), harness side and the clockspring C218-4, circuit 8-PG13 (WH), harness side.




- Measure the resistance between the PCM C175b-48, circuit 9-PG13 (WH), harness side and the clockspring C218-5, circuit 9-PG13 (BN), harness side.




- Are the resistances less than 5 ohms?

Yes
GO to C6.

No
REPAIR the circuit in question. CLEAR the DTCs. TEST the system for normal operation.

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C6 CHECK THE CLOCKSPRING FOR AN OPEN


- Measure the resistance between the clockspring C218 pin 4, component side and the upper clockspring pin 2, component side.




- Measure the resistance between the clockspring C218 pin 5, component side and the upper clockspring pin 3, component side.




- Are the resistances less than 5 ohms?

Yes
INSTALL a new cruise control switch. REFER to Cruise Control Switch Service and Repair. INSTALL the driver air bag module. REFER to Restraint Systems. CLEAR the DTCs. TEST the system for normal operation.

No
INSTALL a new clockspring. INSTALL the driver air bag module. REFER to Restraint Systems. CLEAR the DTCs. TEST the system for normal operation.

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C7 CHECK FOR CORRECT PCM OPERATION


- Connect: All Disconnected Connectors.
- Disconnect all the PCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new PCM. REFER to Computers and Control Systems. INSTALL the driver air bag module. REFER to Restraint Systems. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. INSTALL the driver air bag module. REFER to Restraint Systems.
CLEAR the DTCs. REPEAT the self-test.

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