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

STRTR Relay Control

P0615

P0615

P0615

--

Ground

--

P0615

--

--

Typical Scan Tool Data

Starter Relay Ckt Short Gnd Test Status - ECM

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Cranking

Parameter Normal Value: OK*

STRTR Relay Control

Fault

OK

OK

Ground

--

OK

--

*The parameter displays Not Run when not cranking.


Starter Relay Ckt Open Test Status - ECM

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Value: OK*

STRTR Relay Control

OK

Fault

Fault

Ground

--

Fault

--

*The parameter displays Not Run when cranking.


Starter Relay Ckt Short Volts Test Status - ECM

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Value: OK*

STRTR Relay Control

OK

Fault

Fault

Ground

--

Fault

--

*The parameter displays Not Run when cranking.

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 engine control module (ECM) that crank has been requested. The ECM then verifies that the transmission is in Park or Neutral. If it is, the ECM then supplies 12 V to the control circuit of the STRTR relay. When this occurs, battery voltage is supplied through the switch of the crank relay to terminal A of the starter solenoid.

Conditions for Running the DTC

    • The ignition is ON or in the start position.
    • The system voltage is between 9.5-18 V.

Conditions for Setting the DTC

The ECM detects that the control circuit of the STRTR relay is open, shorted to ground, or shorted to voltage for 2 seconds.

Action Taken When the DTC Sets

DTC P0615 is a type C DTC.

Conditions for Clearing the DTC

DTC P0615 passes when the conditions for setting the DTC are no longer present for 2 seconds.

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

  1. Ignition ON, verify that no immobilizer or automatic transmission DTCs are set that would cause the ECM to disable engine starting.
  2. If any DTCs are set that would inhibit engine starting, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  3. Ignition ON, observe the following scan tool ECM parameters. The scan tool should display the status is OK.
  4. • Starter Relay Ckt Open Test Status
    • Starter Relay Ckt Short Volts Test Status
  5. Turn the ignition switch to the start position. Observe the scan tool ECM Starter Relay Ckt Short Gnd Test Status parameter. The engine should crank, and the scan tool should display the status is OK while the engine is cranking.

Circuit/System Testing

  1. Ignition OFF, disconnect the STRTR relay.
  2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 30 seconds. Test for less than 5 Ω between the ground circuit terminal 85 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition OFF, connect a test lamp between the control circuit terminal 86 and the ground circuit terminal 85.
  5. With the transmission range selector in park or neutral, cycle the ignition key between the OFF and start 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 voltage. If the circuit tests normal, replace the ECM.
    If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  7. If all circuits test normal, test or replace the STRTR relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the STRTR relay.
  2. Test for 60-180 Ω between terminals 85 and 86.
  3. If not within the specified range, replace the relay.
  4. Test for infinite resistance between the following terminals:
  5. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    If not the specified value, replace the relay.
  6. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
  7. If greater than specified range, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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