P0521-ENGINE OIL PRESSURE SENSOR PERFORMANCE
For a complete wiring diagram Refer to Section 8W
- When Monitored:
With the engine running
- Set Condition:
The Engine Control Module (ECM) detects an implausible Engine Oil Pressure Switch signal.
| Possible Causes |
| (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT OPEN |
| (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT SHORT TO GROUND |
| (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT SHORT TO VOLTAGE |
| ENGINE OIL PRESSURE SWITCH |
| ENGINE CONTROL MODULE |
Diagnostic Test
1. CHECK FOR ACTIVE DTCNOTE: If the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.
Incorrect engine oil level may cause this DTC to set. Check and verify that the engine oil level is filled to the proper specification.
Turn the ignition on.
With the scan tool, erase ECM DTCs.
Turn the ignition off, wait 30 seconds, then start and idle the engine for at least 2 minutes.
With the scan tool, read ECM DTCs.
Did this DTC set again?
Yes
- Go To2
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
2. (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT OPEN
Turn the ignition off.
Disconnect the Engine Oil Pressure Switch harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the (G6) Engine Oil Pressure Switch Signal circuit.
Is the resistance below 10.0 ohms?
Yes
- Go To3
No
- Repair the (G6) Engine Oil Pressure Switch Signal circuit for an open.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
3. (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (G6) Engine Oil Pressure Switch Signal circuit.
Is the resistance above 1000 ohms?
Yes
- Go To4
No
- Repair the (G6) Engine Oil Pressure Switch Signal circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
4. (G6) ENGINE OIL PRESSURE SWITCH SIGNAL CIRCUIT SHORTED TO VOLTAGE
Remove the Main Relay.
Connect a jumper wire between cavity B7 and cavity B9 of the Main Relay connector.
Turn the ignition on.
Measure the voltage of the (G6) Engine Oil Pressure Switch Signal circuit.
Is the voltage above 1.0 volt?
Yes
- Repair the (G6) Engine Oil Pressure Switch Signal circuit for a short to voltage.
- Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No
- Go To5
5. CHECKING THE (G6) ENGINE OIL PRESSURE SWITCH SIGNAL VOLTAGE
Reconnect the ECM harness connectors.
Turn the ignition on.
With a voltmeter, measure the voltage of the (G6) Engine Oil Pressure Switch Signal circuit at the Engine Oil Pressure Switch harness connector.
Is the voltage above 10.0 volts?
Yes
- Replace the Engine Oil Pressure Switch.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Replace the ECM in accordance with the Service Information.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).