Clutch Switch Circuit Diagnosis

Clutch Switch Circuit Diagnosis

Diagnostic Instructions

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

Circuit/System Description

The clutch start switch is a normally open switch. When the ignition is ON, B+ is available at terminal 1 of the clutch start switch. When the clutch pedal is depressed, the clutch start switch closes, sending a B+ signal to the engine control module (ECM) to enable engine starting. When the clutch pedal is released, the clutch start switch opens, resulting in zero volts at the ECM and a no start condition.

Diagnostic Aids

This test procedure requires that the battery is completely charged. Refer to Battery Inspection/Test (Battery Inspection/Test).

Reference Information
Schematic Reference

Manual Transmission Schematics (MVC 5 Speed - Manual Transmission)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Powertrain Control Module Scan Tool Information (Scan Tool Testing and Procedures)

Circuit/System Verification

1. Start the engine, with the clutch pedal depressed. The engine should start and run.
2. 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.

Circuit/System Testing

1. Ignition OFF, disconnect the clutch start switch harness connector.
2. Ignition OFF, test for less than 5 ohm between the clutch start switch harness connector terminal 2, and ground.

• If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for 11-13 V on the clutch start switch harness connector terminal 1 and ground.

• If not within the specified range, test the signal circuit for a short to ground, or an open/high resistance.

4. If all circuits test normal, replace the clutch safety switch.

Component Testing

1. Ignition OFF, disconnect the clutch start switch harness connector.
2. Depress the clutch pedal, test for less than 5 ohm between terminals 1 and 2 on the clutch start switch.

• If greater than the specified value, replace the clutch start switch.

Repair Verification

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Powertrain Control Module Replacement (Service and Repair)
* Powertrain Control Module Programming and Setup (Testing and Inspection)