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, then the ECM then supplies 12 volts to the control circuit of the PCM CNTRL relay. When this occurs, battery voltage is supplied through the switch of the PCM CNTRL relay to the terminal A X1 of the starter solenoid. The ECM always supplies some voltage to the control circuit of the PCM CNTRL relay, through a pull-up resistor. If the circuit becomes open or shorted, then the ECM will set DTCs.

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

DTC P0615 is a C type DTC.

DTC P0615 is a C type DTC.

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

1. Ignition ON, verify that no immobilizer or automatic transmission DTCs are set that would cause the ECM not to enable engine starting.
2. Clear the DTCs from the ECM. Turn the ignition to the start position. The engine should crank.
3. Verify that DTC P0615 is not set.

1. Ignition OFF, disconnect the PCM CNTRL relay.
2. With the ignition OFF and the scan tool disconnected, open and close the drivers door, and wait 30 seconds. Test for less than 1.5 ohms between the ground circuit terminal 85 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal 86, and the ground circuit terminal 85.
4. Turn the ignition to the start position. The test lamp should turn ON only when the ignition is held in the start position, for no greater than 10 seconds.

⇒	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.

5. If all circuits test normal, test or replace the PCM CNTRL relay.

PCM CNTRL Relay

1. Ignition OFF, disconnect the PCM CNTRL 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 20A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2.0 ohms between terminals 30 and 87.

⇒	If greater than specified range, replace the relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.