P2539

P2539, P2541, P2542 LOW FUEL PRESSURE SENSOR





DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for at least 60 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Proceed to SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK LOW FUEL PRESSURE SENSOR POWER SUPPLY-I
1. Turn ignition switch OFF.
2. Disconnect low fuel pressure sensor connector.
3. Turn ignition switch ON.
4. Check the voltage between low fuel pressure sensor harness connector terminals.





Inspection result normal?
YES - GO TO 6.
NO - GO TO 2.
2.CHECK LOW FUEL PRESSURE SENSOR POWER SUPPLY-II
Check the voltage between low fuel pressure sensor harness connector and the ground.





Is inspection result normal?
YES - GO TO 4.
NO - GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness connector for short to power and short to ground, between the following terminals.





Is inspection result normal?
YES - Perform the trouble diagnosis for power supply circuit. Power Supply And Ground Circuit.
NO - Repair or replace error-detected parts.
4.CHECK LOW FUEL PRESSURE SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between low fuel pressure sensor harness connector and ECM harness connector.





Is inspection result normal?
YES - GO TO 5.
NO - Repair or replace error-detected parts.
5.CHECK ECM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ECM harness connector and the ground.





Is inspection result normal?
YES - Check intermittent incident. Intermittent Incident.
NO - Repair or replace error-detected parts.
6.CHECK LOW FUEL PRESSURE SENSOR SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between low fuel pressure sensor harness connector and ECM harness connector.





4. Also check harness for short to ground and to power.
Is inspection result normal?
YES - GO TO 7.
NO - Repair or replace error-detected parts.
7.CHECK LOW FUEL PRESSURE SENSOR
SEE Component Inspection.
Is inspection result normal?
YES - Check intermittent incident. Intermittent Incident.
NO - Replace low fuel pressure sensor.




Component Inspection
1.CHECK LOW FUEL PRESSURE SENSOR
WITH CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect harness connector disconnected.
3. Start the engine.
4. Select "DATA MONITOR" mode with CONSULT-III.
5. Check that the "L/FUEL PRES SEN V" value.





WITHOUT CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect harness connector disconnected.
3. Start the engine.
4. Check low fuel pressure sensor signal voltage.






Is the inspection result normal?
YES - INSPECTION END.
NO - Replace low fuel pressure sensor.