Pinpoint Test A: The Speed Control Is Inoperative
Speed Control
Pinpoint Tests
Pinpoint Test A: The Speed Control Is Inoperative
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 VES10 (WH) to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit RES08 (GN/BN) and the clockspring. When the brake pedal is applied the PCM deactivates the speed control if engaged.
The speed control deactivator switch (part of the stoplamp switch) interrupts circuit CES09 (VT/OG) removing the voltage signal to the PCM when the brake pedal is applied. This is a redundant signal to the PCM.
Vehicles equipped with a manual transaxle have an additional clutch pedal speed control deactivator switch. The PCM sends a signal through circuit CE904 (GN/VT) to the clutch pedal speed control deactivator switch. The return signal is sent to the PCM through circuit RE407 (YE/VT).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- PCM not configured for speed control
- Stoplamp switch
- Clutch Pedal Position (CPP) switch
- Speed control switch
- Digital Transmission Range (TR) sensor
- Vehicle speed signal
- PCM
PINPOINT TEST A: THE SPEED CONTROL IS INOPERATIVE
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A1 VERIFY PCM CONFIGURATION
- Enter the following diagnostic mode on the scan tool: Programmable Parameters.
- Verify that the speed control is enabled in the PCM.
- Is the speed control enabled?
Yes
GO to A2.
No
ENABLE the speed control in the PCM using the scan tool programmable parameters menu. TEST the system for normal operation.
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A2 CHECK FOR DTCs
- Review the recorded DTCs from the PCM self-test.
- Are any non-speed control DTCs recorded?
Yes
REFER to Computers and Control Systems Information. REPAIR all PCM DTCs and RETEST the speed control.
No
GO to A3.
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A3 CHECK THE VEHICLE SPEED
- Check for correct operation of the speedometer.
- Does the speedometer operate correctly?
Yes
GO to A4.
No
REFER to the Instrument Panel, Gauges and Warning Indicators to diagnose the speedometer.
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A4 CHECK THE STOPLAMP SWITCH (BOO AND BPA) PIDs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Monitor the PCM PIDs BOO (brake pedal top travel) and BPA (brake pedal bottom travel). while applying and releasing the brake pedal as follows:
- Do the PID values agree with the brake pedal position?
Yes
If equipped with an automatic transaxle, GO to A6.
If equipped with a manual transaxle, GO to A5.
No
Go To Pinpoint Test B. Pinpoint Test B: DTC P1572 or DTC P1703
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A5 CHECK THE CPP SWITCH (CPP_TOP) PID
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Monitor the PCM PID CPP_TOP while pressing and releasing the clutch pedal.
- Does the PID value agree with the clutch pedal position?
Yes
GO to A7.
No
Go To Pinpoint Test D. Pinpoint Test D: The Speed Control Does Not Disengage When the Clutch Is Applied
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A6 MONITOR THE TR PID
- Enter the following diagnostic mode on the scan tool: Transmission Control Module (TCM) DataLogger.
- Monitor the TCM PID (TR).
- Select DRIVE.
- Does the PID value agree with the TR selector lever position?
Yes
GO to A7.
No
REFER to Transmission Control Systems to continue diagnosis of the digital TR sensor. Testing and Inspection
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A7 CHECK THE SPEED CONTROL SWITCH
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Press each speed control switch while monitoring the speed control switch PID (SCCS).
- Does the PID value agree with the switch position?
Yes
GO to A8 .
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 Pinpoint Test C. Pinpoint Test C: The Speed Control Switches Do Not Operate Correctly
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A8 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 Computers and Control Systems Information. 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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