Starter Solenoid Does Not Click
Starter Solenoid Does Not Click
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.
Diagnostic Fault Information
Circuit/System Description
When the ignition mode 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 serial data message to the engine control module (ECM) that crank has been requested. The ECM then verifies that the clutch is fully depressed or the automatic transmission is in Park/Neutral. If it is, the ECM then supplies 12 V 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.
Reference Information
Schematic Reference
* Starting and Charging Schematics [1][2]Electrical Diagrams
* Automatic Transmission Controls Schematics Electrical Diagrams
Connector End View Reference
Component Connector End Views 5 Bow Lowered Switch (CM7)
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
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, verify that no starter relay, clutch pedal position sensor, brake pedal position sensor, theft deterrent, or automatic transmission DTCs are set that would cause the ECM to disable engine starting.
• If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle
2. Ignition ON, observe the scan tool BCM Current Power Mode parameter. Place ignition mode switch in the crank position, the parameter should display Crank Request.
• If not the specified value, refer to Power Mode Description and Operation Power Mode
3. Ignition ON, observe the scan tool ECM clutch pedal parameter, verify the scan tool parameter displays Applied / Released while depressing and releasing the clutch pedal.
• If the clutch pedal parameter does change. Refer to Clutch Pedal Position Sensor Learn Testing and Inspection
4. Transmission range selector in park , verify the scan tool ECM PNP Switch and TCM IMS parameters display Park/Neutral.
• If the TCM IMS parameter does not indicate Park/Neutral. Refer to Transmission Internal Mode Switch Logic Transmission Internal Mode Switch Logic
• If the ECM Park/Neutral parameter does not indicate Park/Neutral. Refer to ECM Park Switch Circuit Malfunction.
5. Transmission range selector in park or neutral, or clutch pedal fully depressed attempt to start the vehicle. The crank relay should click and the engine should begin cranking.
• If the crank relay does not click or the engine does not crank, refer to Crank Relay Circuit Malfunction.
Circuit/System Testing
ECM Park Switch Circuit Malfunction (6L50-E / 6L80-E / 6L90-E)
1. Ignition OFF, disconnect the harness connector at the AT Inline 16-Way (6L50-E / 6L80-E / 6L90-E) at the transmission.
2. Ignition ON, test for B+ between terminal 3 and ground. (note this circuit will not light a test lamp).
• If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
3. If all circuits test normal, test or replace the internal mode switch (IMS).
Crank Relay Circuit Malfunction
1. Ignition OFF, disconnect the crank relay.
2. Ignition OFF, test for less than 5.0 omhs between the relay ground circuit terminal 85 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 relay switch 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. Ensure the parking brake is applied and the transmission is in NEUTRAL on manual transmission or PARK on automatic transmissions. Momentarily install a 40A fused jumper wire between the B+ circuit terminal 30 and the control output circuit terminal 87. The starter solenoid should engage and the engine should begin cranking.
• If the solenoid does not engage, test the control output circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the starter motor.
5. Connect a test lamp between the coil control circuit terminal 86 and the coil ground circuit terminal 85.
6. With the transmission range selector in park/neutral, or the clutch pedal fully depressed, place the ignition mode switch 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 a 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 crank relay.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Manual Shift Shaft Position Switch Replacement Service and Repair
* 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 Control Module References for ECM replacement, setup, and programming