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 volts to the control circuit of the CRNK relay. When this occurs, battery voltage is supplied through the switch of the crank relay to terminal A X1 of the starter solenoid. The ECM monitors the voltage on the CRNK relay control circuit. If the voltage is not what is expected, then DTC P0615 sets.

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

DTC P0615 is a type C DTC.

DTC P0615 is a type C DTC.

Inspect ground connection G105. Verify that it is clean and tight.

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Observe the scan tool ECM Starter Relay Circuit Test Status parameters. Verify that the scan tool does not display any circuit faults.

1. Ignition OFF, disconnect the CRNK relay.
2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the relay ground circuit terminal 85 and ground.

⇒	If not within the specified range, test the ground circuit for an open/high resistance.

3. Ignition OFF, connect a test lamp between the control circuit terminal 86 and the ground circuit terminal 85. Turn the ignition to the start position. The test lamp should illuminate for a maximum of 10 seconds when the ignition is held in the start position.

⇒	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.

4. If all circuits test normal, test or replace the CRNK relay.

CRNK Relay

1. Ignition OFF, disconnect the CRNK relay.
2. Test for 60-180 ohms between terminals 85 and 86.

⇒	If not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

•

30 and 86

•

30 and 87

•

30 and 85

•

85 and 87

⇒	If not the specified value, replace the relay.

4. Install a 20 amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.

⇒	If greater than specified range, replace the relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.