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

Control

P0615

P0615

P0615

--

Circuit/System Description

When the ignition switch is placed in the START position, a discrete signal is supplied to the body control module (BCM) notifying it that the ignition is in the START position. The BCM then sends a message to the powertrain control module (PCM) that crank has been requested. The PCM then verifies that the transmission is in Park or Neutral. If it is, the PCM then supplies a ground to the control circuit of the crank relay. When this occurs, battery voltage is supplied through the switch of the crank relay to the starter solenoid.

Conditions for Running the DTC

    • The ignition is in the START position.
    • The system voltage is between 9.5-18 V.

Conditions for Setting the DTC

The PCM detects improper voltage on the control circuit of the crank 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 Verification

Ignition ON, verify that no theft deterrent or automatic transmission DTCs are set that would cause the PCM not to enable engine starting.

Circuit/System Testing

  1. Ignition OFF, disconnect the CRANK relay,
  2. Ignition ON, verify a test lamp illuminates between the crank relay coil supply voltage circuit terminal M4 and ground.
  3. If , test lamp does not illuminate, test the supply voltage circuit for a short to ground or an open/high resistance.
  4. Ignition ON, connect a test lamp between the crank relay coil supply voltage terminal M4 and the crank relay control circuit terminal K5.
  5. With the transmission range selector in park or neutral, cycle the ignition between the OFF and CRANK position. The test lamp should turn ON and OFF when changing between the commanded states.
  6. If the test lamp is always ON, test the control circuit for short to ground. If the circuits test normal replace the PCM.
    If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuits test normal replace the PCM.
  7. If the circuits test normal replace the crank relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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