2000 - 2999: 2502
2502-PRESSURE REGULATOR VALVE CIRCUIT SHORT TO GROUND
For a complete wiring diagram, Refer to the Wiring Information Electrical Diagrams.
- When Monitored:
With the ignition on and the Boost Pressure Servo Motor command off.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, clear DTCs in the Engine Control Module (ECM).
3. With the scan tool, actuate the Boost Pressure Servo Motor.
4. Monitor the scan tool for at least two minutes.
5. With the scan tool, select View DTCs.
Is the status Active for this DTC?
Yes
- Go To 2
No
- Perform the INTERMITTENT DTC diagnostic procedure. .
2. FUSED ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Boost Pressure Servo Motor harness connector.
3. Turn the ignition on.
4. Using a 12-volt test light connected to ground, check the Fused ASD Relay Output circuit in the Boost Pressure Servo Motor harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test light illuminated and bright?
Yes
- Go To 3
No
- Repair the Fused ASD Relay Output circuit for an open circuit or high resistance.
- Perform the ECM Verification Test. Verification Tests.
3. BOOST PRESSURE SERVO MOTOR CONTROL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Engine Control Module (ECM) harness connector.
3. Measure the resistance between ground and the Boost Pressure Servo Motor Control circuit in the Boost Pressure Servo Motor harness connector.
Is the resistance above 1000 Ohms?
Yes
- Go To 4
No
- Repair the Boost Pressure Servo Motor Control circuit for a short to ground.
- Perform the ECM Verification Test. Verification Tests.
4. BOOST PRESSURE SERVO MOTOR CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
1. Measure the resistance of the Boost Pressure Servo Motor Control circuit between the Boost Pressure Servo Motor harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 Ohms?
Yes
- Go To 5
No
- Repair the Boost Pressure Servo Motor Control circuit for an open circuit or high resistance.
- Perform the ECM Verification Test. Verification Tests.
5. BOOST PRESSURE SERVO MOTOR
1. Turn the ignition off.
2. Connect the Engine Control Module (ECM) harness connector.
3. Turn the ignition on.
4. With the scan tool, actuate the Boost Pressure Servo Motor (Boost Pressure Actuator) to 100%.
5. Using a 12-volt test light connected to 12 volts, check the Boost Pressure Servo Motor Control circuit in the Boost Pressure Servo Motor harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
NOTE: The circuit will remain actuated by the controller for 30 seconds. Be certain the actuation is active when checking the circuit.
6. With the scan tool, actuate the Boost Pressure Servo Motor (Boost Pressure Actuator) to 0%.
7. Using a 12-volt test light connected to 12 volts, check the Boost Pressure Servo Motor Control circuit in the Boost Pressure Servo Motor harness connector.
NOTE: The test light should not be illuminated.
NOTE: The circuit will remain actuated by the controller for 30 seconds. Be certain the actuation is active when checking the circuit.
Is the test light illuminated and bright with the actuation at 100% and not illuminated with the actuation at 0%?
Yes
- Replace the Boost Pressure Servo Motor.
- Perform the ECM Verification Test. Verification Tests.
No
- Go To 6
6. ENGINE CONTROL MODULE (ECM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Boost Pressure Servo Motor and the Engine Control Module (ECM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the ECM Verification Test. Verification Tests.
No
- Replace the Engine Control Module (ECM).
- Perform the ECM Verification Test. Verification Tests.