P0615
DTC P0615
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0615
- Starter Relay Control Circuit
Diagnostic Fault Information
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 clutch pedal is depressed or the transmission is in Park/Neutral. If it is, the ECM then supplies 12 V to the control circuit of the starter relay. When this occurs, battery voltage is supplied through the switch of the starter 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 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 (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
Starting System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Ignition ON, verify that no theft deterrent or automatic transmission DTCs are set that would cause the ECM not to enable engine starting.
Circuit/System Testing
1. Ignition OFF, disconnect the KR27 starter relay.
2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 10 Ohms between the relay ground circuit terminal 86 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 30 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
5. Parking brake applied, transmission in neutral or park. Momentarily install a 30 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the starter is activated.
• If the starter does not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the M64 starter.
6. Ignition OFF, connect a test lamp between the control circuit terminal 85 and the ground circuit terminal 86.
7. 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.
• If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the K20 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 K20 ECM.
8. If all circuits tests normal, replace the KR27 starter relay.
Component Testing
Relay Test
1. Ignition OFF, disconnect the KR27 starter 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 5 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 Ohms between terminals 30 and 87.
• If greater than specified range, replace the relay.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming