GM Service Manual Online
For 1990-2009 cars only

Object Number: 1578593  Size: LF
Master Electrical Component List
Manual Transmission Schematics
OBD II Symbol Description Notice
Control Module References

Circuit Description

The clutch pedal position (CPP) sensor is an input to the engine control module (ECM). The CPP sensor is a potentiometer type sensor with a 5-volt reference signal circuit, a low reference signal circuit and a sensor signal circuit. The ECM supplies the 5-volt reference signal to the CPP sensor.

With the pedal released the CPP sensor signal should read above 4 volts. With the pedal fully depressed the CPP sensor signal should read below 1 volt.

When the ECM detects a stuck CPP sensor, DTC P0806 sets. DTC P0806 is a type A DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0806 Clutch Position Sensor Circuit Range/Performance

Conditions for Running the DTC

    • No CKP sensor DTCs P0335 or P0336.
    • No VSS DTCs P0502 and P0503.
    • No CPP sensor DTCs P0807, P0808, and P080A.
    • The vehicle is in gear.

Conditions for Setting the DTC

The ECM detects a clutch position error greater than 5 percent for greater than 6 seconds.

Action Taken When the DTC Sets

    • The ECM illuminates the malfunction indicator lamp (MIL).
    • The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
    • The ECM stores DTC P0806 in ECM history.

Conditions for Clearing the DTC

    • The ECM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
    • A scan tool can clear the MIL/DTC.
    • The ECM clears the DTC from ECM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.

Diagnostic Aids

    • Use the J 35616 GM-approved Terminal Test Kit for any test that requires probing the ECM harness connector or any component connector.
    • A malfunctioning or damaged CPP Sensor may cause this DTC to set.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests for the current state of the CPP sensor.

Step

Action

Values

Yes

No

Schematic Reference:   Antilock Brake System Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure records for reference. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM.

  4. Use the scan tool to monitor the CPP Sensor parameter in the manual transmission data list.

Does the scan tool display a voltage within the specified range?

4.8-5.2 V

Go to Step 3

Go to Step 4

3

  1. Observe the Freeze Frame and Failure Records for the DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame and Failure Records.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Important: DO NOT use any mechanical device such as pliers or screwdrivers to disengage the connector. In order to prevent damage to the connector or harness wiring, both of the latches on the connector must be depressed with finger pressure only. When the latches are depressed the connector must then be pulled straight back without pulling on the wires in order to disengage. Failure to follow this procedure can lead to connector or wiring harness damage and failure.

  3. Disconnect the CPP sensor connector.
  4. Turn ON the ignition, with the engine OFF.
  5. Connect a DMM between the 5 volt reference circuit of the CPP sensor connector and ground.

Is the voltage more than the specified value?

4.8 V

Go to Step 5

Go to Step 8

5

Connect a 3-amp fused jumper wire between the 5-volt reference signal circuit and the CPP sensor signal circuit of the CPP sensor connector. Observe the CPP Sensor parameter, with a scan tool.

Is the voltage more than the specified value?

4.8 V

Go to Step 6

Go to Step 7

6

Connect a DMM between the 5-volt reference circuit and the low reference circuit of the CPP sensor connector.

Is the voltage greater than the specified value?

4.8 V

Go to Step 10

Go to Step 9

7

Test the CPP sensor signal circuit of the CPP sensor for high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 11

8

Test the 5-volt reference signal circuit of the CPP sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 11

9

Test the low reference signal circuit of the CPP sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 11

10

Test for an intermittent and for a poor connection at the CPP sensor connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 12

11

Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

12

Important: The CPP sensor learn procedure is required when the following service procedures have been performed regardless of whether DTC P080A is set:

   • An ECM replacement
   • A CPP sensor replacement
   • Any repairs which affect the CPP sensor relationship

Replace the CPP sensor. Refer to Clutch Pedal Replacement .

Did you complete the replacement?

--

Go to Step 14

--

13

Replace the ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 14

--

14

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Turn ON the ignition with the engine OFF.
  4. Select specific DTC.
  5. Enter DTC P0806.
  6. Start the engine.
  7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame and Failure Records.

did the DTC fail this ignition?

--

Go to Step 2

Go to Step 15

15

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK