Pinpoint Test A: The Cruise Control Is Inoperative
Cruise Control
Pinpoint Tests
Pinpoint Test A: The Cruise Control Is Inoperative
Refer to Wiring Diagram Set 31, Cruise Control for schematic and connector information. Diagrams By Number
Normal Operation
The cruise control switches uses the PCM RUN/START voltage and the PCM ground. The cruise control functionality is controlled through the cruise control switches and is hard-wired to the PCM through a signal and return circuit.
There are 5 cruise control switches with each switch operating a specific function that uses different resistance values. The PCM sends out a reference voltage to the cruise control switches and monitors the voltage drop when a cruise control switch is pressed. The voltage drop varies depending upon the resistance of each switch, providing a specific indication to the PCM which switch is pressed, activating and controlling the cruise control system.
The stoplamp switch is a single plunger 2 stage switch with 2 inputs to the PCM. When the brake pedal is applied, the first stage, which is a normally open stoplamp switch, closes and sends a voltage signal to the PCM deactivating the cruise control, if engaged. The second stage is the normally closed cruise control deactivator switch (integral to the stoplamp switch) opens and removes the ground signal to the PCM when the brake pedal is firmly applied. This is a redundant signal to the PCM. There is less than one millimeter in plunger travel between the first and second stage which the PCM monitors.
Vehicles equipped with a manual transmission have an additional clutch pedal cruise control deactivator switch. The clutch pedal cruise control deactivator switch provides a ground signal to the PCM. When the clutch pedal is applied the normally closed clutch pedal cruise control deactivator switch opens and removes the ground signal to the PCM which deactivates the cruise control, if engaged.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals and connectors
- PCM not configured for cruise control
- Clutch pedal cruise control deactivator switch (manual transmission)
- Cruise control deactivator switch (integral to the stoplamp switch)
- Cruise control switches
- Digital Transmission Range (TR) sensor system concern (automatic transmission)
- Stoplamp switch
- PCM
PINPOINT TEST A: THE CRUISE CONTROL IS INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery, Mounting and Cables Service and Repair.
-------------------------------------------------
A1 CHECK FOR DTCs
- Review the recorded DTCs from the PCM self-test.
- Are any PCM DTCs recorded?
Yes
REFER to DTC Charts. Diagnostic Trouble Code Tests and Associated Procedures
No
GO to A2.
-------------------------------------------------
A2 CHECK FOR ABS MODULE DTCs
- Review the recorded DTCs from the ABS module self-test.
- Are any DTCs recorded?
Yes
REFER to Vehicle Dynamic Systems Diagnostic Trouble Code Tests and Associated Procedures. REPAIR all ABS module DTCs and RETEST the system.
No
GO to A3.
-------------------------------------------------
A3 CHECK THE STOPLAMP SWITCH (BOO1) AND CRUISE CONTROL DEACTIVATOR SWITCH (BOO2) PIDs
- Enter the following diagnostic mode on the scan tool: PCM DataLogger .
- Monitor the PCM PIDs BOO1 (stoplamp switch) and BOO2 (cruise control deactivator switch) while applying and releasing the brake pedal as follows:
- Does the PID value agree with the brake pedal position?
Yes
GO to A4.
No
GO to Pinpoint Test B. Pinpoint Test B: DTC P0504, P0572 Or P0573
-------------------------------------------------
A4 CHECK THE CRUISE CONTROL SWITCH
- Enter the following diagnostic mode on the scan tool: PCM DataLogger .
- Press each cruise control switch button while monitoring the SCCS PID (cruise control switch).
- Does the PID value agree with the switch position?
Yes
If equipped with an automatic transmission, GO to A5.
If equipped with a manual transmission, GO to A6.
No
If only one switch does not display the correct PID value, INSTALL a new cruise control switch. REFER to Cruise Control Switch Cruise Control Switch. TEST the system for normal operation.
Otherwise, GO to Pinpoint Test C. Pinpoint Test C: DTC P0579 Or DTC P0581
-------------------------------------------------
A5 CHECK THE DIGITAL TR SENSOR PID
- Enter the following diagnostic mode on the scan tool: PCM DataLogger .
- Monitor the PCM TR PID.
- Select DRIVE.
- Does the PID value agree with the transmission range selector lever position?
Yes
GO to A9.
No
REFER to Automatic Transaxle/Transmission - 6R80 Testing and Inspection to diagnose the TR input concern.
-------------------------------------------------
A6 CHECK THE CLUTCH PEDAL CRUISE CONTROL DEACTIVATOR SWITCH PID (CPP_TOP)
- Enter the following diagnostic mode on the scan tool: PCM DataLogger .
- Monitor the PCM CPP_TOP PID while pressing and releasing the clutch pedal.
- Does the clutch pedal cruise control deactivator switch PID agree with the clutch pedal position?
Yes
GO to A9.
No
GO to A7.
-------------------------------------------------
A7 CHECK THE CLUTCH PEDAL CRUISE CONTROL DEACTIVATOR SWITCH GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable .
- Disconnect: Clutch Pedal Cruise Control Deactivator Switch C277 .
- Measure the resistance between the clutch pedal cruise control deactivator switch C277-3, circuit GD129 (BK/YE), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to A8.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
A8 CHECK THE CLUTCH PEDAL CRUISE CONTROL DEACTIVATOR SWITCH SIGNAL CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: PCM C175t .
- Measure the resistance between the PCM C175t-21, circuit CE904 (GN/VT), harness side and the clutch pedal cruise control deactivator switch C277-1, circuit CE904 (GN/VT), harness side; and between the PCM C175t-21, circuit CE904 (GN/VT), harness side and ground.
- Is the resistance less than 5 ohms between the PCM and the clutch pedal cruise control deactivator switch, and greater than 10,000 ohms between the PCM and ground?
Yes
INSTALL a new clutch pedal cruise control deactivator switch. REFER to Cruise Control Deactivator Switch Cruise Control Deactivator Switch. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
A9 CHECK FOR CORRECT PCM OPERATION
- 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 Electronic Engine Controls Service and Repair. 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.
-------------------------------------------------