Pinpoint Test C: The Speed Control Switches Do Not Operate Correctly
Speed Control
Pinpoint Test C: The Speed Control Switches Do Not Operate Correctly
Refer to Wiring Diagram Set 31, Speed Control for schematic and connector information. Diagrams By Number
Normal Operation
The PCM sends a signal through circuit 151 (LB/BK) to the speed control switches, which passes through the clockspring. The return signal is sent through circuit 848 (DG/OG) and the clockspring.
- DTC P0579 (Cruise Control Multifunction Input A Circuit Range/Performance) - sets when the speed control switch circuits are open, shorted to voltage or ground.
- DTC P0581 (Cruise Control Multi-Function Input A Circuit High) - sets when the speed control switch circuits are open or shorted to voltage.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Speed control switches
- Clockspring
- PCM
PINPOINT TEST C: THE SPEED 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 SPEED CONTROL SWITCH
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Press each speed control switch button while monitoring the speed control switch PID (SCCS).
- Does the PID value agree with the switch position?
Yes
GO to C14.
No
If only one switch does not display the correct PID value, INSTALL a new speed control switch. REFER to Speed Control Switch Speed Control Switch. TEST the system for normal operation.
Otherwise, GO to C2.
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C2 CHECK THE SPEED CONTROL SWITCH CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: PCM C175b.
- Ignition ON.
- Turn the parking lamps on.
- Measure the voltage between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Is any voltage present?
Yes
TURN the parking lamps off. GO to C3.
No
TURN the parking lamps off. GO to C6.
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C3 CHECK CIRCUITS 151 (LB/BK) AND 848 (DG/OG) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Clockspring C218a.
- Ignition ON.
- Turn the parking lamps on.
- Measure the voltage between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test.
No
TURN the parking lamps off. GO to C4.
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C4 CHECK THE CLOCKSPRING FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Connect: Clockspring C218a.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
- Remove the driver air bag module.
- Connect the restraint system diagnostic tools (418-F395) to the upper clockspring.
- Disconnect: Clockspring C218b.
- Connect the battery.
- Ignition ON.
- Turn the parking lamps on.
- Measure the voltage between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Is any voltage present?
Yes
INSTALL a new clockspring. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
GO to C5.
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C5 CHECK THE STEERING WHEEL HARNESS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Connect: Clockspring C218b.
- Disconnect: Speed Control Switch(es).
- Ignition ON.
- Turn the parking lamps on.
- If equipped with remote audio/climate control switches, measure the voltage between the speed control switch C203, harness side and ground as follows:
- If not equipped with remote audio/climate control switches, measure the voltage between the speed control switch C2330a, harness side and ground as follows:
- Is any voltage present?
Yes
REPAIR the circuit in question. DISCONNECT the battery. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
INSTALL a new speed control switch(es). REFER to Speed Control Switch Speed Control Switch. DISCONNECT the battery. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
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C6 CHECK THE SPEED CONTROL SWITCH CIRCUITRY FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Are the resistances greater than 10,000 ohms?
Yes
GO to C10.
No
GO to C7.
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C7 CHECK THE CLOCKSPRING FOR A SHORT TO GROUND
- Remove the driver air bag module.
- Disconnect: Clockspring C218b.
- Measure the resistance between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Are the resistances greater than 10,000 ohms?
Yes
GO to C9.
No
GO to C8.
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C8 CHECK CIRCUITS 151 (LB/BK) AND 848 (DG/OG) FOR A SHORT TO GROUND
- Disconnect: Clockspring C218a.
- Measure the resistance between the PCM C175b-19, circuit 151 (LB/BK), harness side and ground; and between the PCM C175b-30, circuit 848 (DG/OG), harness side and ground.
- Are the resistances greater than 10,000 ohms?
Yes
INSTALL a new clockspring. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test.
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C9 CHECK THE SPEED CONTROL SWITCH FOR A SHORT TO GROUND
- Disconnect: Speed Control Switch(es).
- If equipped with remote audio/climate control switches, measure the resistance between the speed control switch C203, harness side and ground as follows:
- If not equipped with remote audio/climate control switches, measure the resistance between the speed control switch C2330a, harness side and ground as follows:
- Are the resistances greater than 10,000 ohms?
Yes
INSTALL a new speed control switch(es). REFER to Speed Control Switch Speed Control Switch. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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C10 CHECK THE SPEED CONTROL SWITCH CIRCUITRY FOR AN OPEN
- Measure the resistance between the PCM C175b-19, circuit 151 (LB/BK), harness side and the PCM C175b-30, circuit 848 (DG/OG), harness side.
- Is the resistance between 3,965 and 4,655 ohms?
Yes
GO to C13.
No
GO to C11.
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C11 CHECK CIRCUITS 151 (LB/BK) AND 848 (DG/OG) FOR AN OPEN
- Disconnect: Clockspring C218a.
- Measure the resistance between the PCM C175b-19, circuit 151 (LB/BK), harness side and the clockspring C218a-13, circuit 151 (LB/BK), harness side.
- Measure the resistance between the PCM C175b-30, circuit 848 (DG/OG), harness side and the clockspring C218a-3, circuit 848 (DG/OG), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to C12.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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C12 CHECK THE CLOCKSPRING
- Remove the driver air bag module.
- Disconnect: Clockspring C218b.
- Measure the resistance between the clockspring C218b pin 11, component side and the clockspring C218a pin 3, component side.
- Measure the resistance between the clockspring C218b pin 3, component side and the clockspring C218a pin 13, component side.
- Are the resistances less than 5 ohms?
Yes
GO to C13.
No
INSTALL a new clockspring. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
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C13 CHECK THE STEERING WHEEL HARNESS
- Disconnect: Speed Control Switch(es).
- If equipped with remote audio/climate control switches, measure the resistance between the clockspring C218b, harness side and the speed control switch C203, harness side as follows:
- If not equipped with remote audio/climate control switches, measure the resistance between the clockspring C218b, harness side and the speed control switch; and between the speed control switch C2330a, harness side and the speed control switch C2330b, harness side as follows:
- Are the resistances less than 5 ohms?
Yes
INSTALL new speed control switch(es). REFER to Speed Control Switch Speed Control Switch. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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C14 CHECK FOR CORRECT PCM OPERATION
- Connect: All Disconnected Connectors.
- Install the driver air bag module.
- 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. 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.
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