GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0806: Clutch Pedal Position (CPP) Sensor Circuit Performance

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

CPP Sensor Signal

P0807

P0807

P0808

P0806

CPP Sensor 5-Volt Reference

P0651, P0807

P0807

P0651, P0808

--

CPP Sensor Low Reference

--

P0808

P0808

--

Typical Scan Tool Information

CPP Sensor Voltage

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON.

CPP Sensor Voltage Parameter Normal Range: 0-volts with clutch pedal applied to 5-volts when clutch pedal is released.

CPP Sensor 5-Volt Reference

0 volts

0 volts

5 volts

CPP Sensor Signal

0 volts

0 volts

5 volts

CPP Sensor Low Reference

--

5 volts

--


CPP Sensor Percentage

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON.

CPP Sensor Percent Parameter Normal Range: 0% with clutch pedal released to 100% when clutch pedal is applied.

CPP Sensor 5-Volt Reference

100%

100%

0-100%

CPP Sensor Signal

100%

100%

100%

CPP Sensor Low Reference

--

0%

--

Circuit/System Description

The clutch pedal position (CPP) sensor is a three wire sensor, connected to a 5-volt reference circuit, a low reference circuit, and a signal circuit. The engine control module (ECM) supplies 5 volts to the CPP sensor, and also provides a sensor ground path on the low reference circuit. The CPP sensor sends a voltage signal to the ECM on the signal circuit. The voltage on the signal circuit will vary from a voltage less than or equal to 5 volts when the clutch pedal is released, to a voltage less than or equal to 1.5 volt when the clutch pedal is applied.

Conditions for Running the DTC

DTCs P0335, P0336, P0502, P0503, P0607, P0808, or P080A are not set.

Conditions for Setting the DTC

The CPP sensor is stuck in range.

Action Taken When the DTC Sets

P0806 is a Type A DTC.

Conditions for Clearing the MIL/DTC

P0806 is a Type A DTC.

Reference Information

Schematic Reference

Manual Transmission Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Transmission System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, observe the scan tool CPP sensor percent parameter. The percentage should vary from 0% when the clutch pedal is released, to 100% when the clutch pedal is in the apply position.
  2. Perform the CPP learn procedure. Refer to Clutch Pedal Position Sensor Learn.
  3. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector of the CPP sensor.
  2. Ignition ON, observe the scan tool CPP sensor voltage parameter for 0.1-volt.
  3. If the voltage is below the specified value, replace the CPP sensor.
    If the voltage is above the specified value, replace the ECM.

Component Testing

  1. Ignition OFF, disconnect the harness connector of the CPP sensor.
  2. Measure the resistance between the signal terminal B and the low reference terminal A of the CPP sensor. Sweep the CPP sensor through the entire range. The resistance should vary low to high and high to low without any spikes or dropouts.
  3. If the resistance is erratic with spikes or dropouts, replace the CPP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Clutch Pedal Replacement
    •  Control Module References for ECM replacement, setup and programming