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 P0615: Starter Relay Control Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Starter Relay Control

P0615

P0615

P0615

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Circuit/System Description Automatic Transmission

When the Ignition switch is placed in the start position B+ is supplied to the coil side of the STARTER relay, the powertrain control module (PCM) / engine control module (ECM) also receives the 12 V signal that crank has been requested, The PCM/ECM verifies the vehicle is in PARK from information received from the transmission control module (TCM) and conditions are acceptable for engine cranking, the PCM/ECM will then ground the control circuit of the STARTER relay. With STARTER relay closed B+ is supplied to the starter solenoid and the engine will begin cranking.

Circuit/System Description Manual Transmission

When the Ignition switch is placed in the start position and Clutch Start Switch closed (clutch pedal depressed) B+ is supplied to the coil side of the STARTER relay, the powertrain control module (PCM) / engine control module (ECM) also receives the 12 V signal that crank has been requested, The PCM/ECM verifies the clutch pedal is depressed and conditions are acceptable for engine cranking, the PCM/ECM will then ground the control circuit of the STARTER relay. With STARTER relay closed B+ is supplied to the starter solenoid and the engine will begin cranking.

Conditions for Running the DTC

    • The Ignition is in the START position.
    • The system voltage is between 9.5-18 volts.

Conditions for Setting the DTC

The ECM detects improper voltage on the control circuit of the starter relay.

Action Taken When the DTC Sets

DTC P0615 is a C type DTC.

Conditions for Clearing the DTC

DTC P0615 is a C type DTC.

Reference Information

Schematic Reference

Starting and Charging Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Starting 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 Testing

  1. Ignition ON, verify DTC P0615 is set as current.
  2. Ignition OFF, disconnect the crank relay, test for 60-80 ohms of resistance between relay terminals 85 and 86.
  3. If not within the specified range, replace the crank relay.
  4. Ignition ON, connect a test lamp between B+ and the crank relay control circuit terminal B9. Place the ignition to the start position. The test lamp should only illuminate when the ignition is held in the start position.
  5. If the test lamp is always On, test the control circuit for short to ground.
    If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance.
    If the circuit tests normal replace the ECM/PCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement
    •  Control Module References for ECM/PCM replacement, setup, and programming