Savana 3500 V8-6.6L DSL Turbo VIN 6 (2007)
High Idle Switch: Testing and Inspection
High Idle Switch Diagnosis
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 provide an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Verification
Ignition ON, observe the scan tool High Idle switch parameter while exercising the switch. The reading should change between ON/OFF.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the high idle switch.
2. Test for less than 5 ohms of resistance between the ground circuit terminal A and ground.
‹› If greater than 5 ohms, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool High Idle switch parameter is OFF.
‹› If not OFF, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM.
4. Install a 3A fused jumper wire between the signal circuit terminal C and ground. Verify the scan tool High Idle switch parameter is ON.
‹› If not ON, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If all circuits test normal, test or replace the high idle switch.
Component Testing
1. Ignition OFF, disconnect the harness connector at the high idle switch.
2. Test for infinite resistance between the signal terminal C and the ground circuit terminal A with the switch in the open position.
‹› If less than infinite resistance, replace the high idle switch.
3. Test for less than 1 ohm between the signal terminal C and the ground terminal A with the switch in the closed position.
‹› If greater than 1 ohm, replace the high idle switch.
