P0521-ENGINE OIL PRESSURE SENSOR PERFORMANCE
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For a complete wiring diagram, refer to the Wiring Information.
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When Monitored:
Engine running.
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Set Condition:
The engine oil pressure never reaches the calibrated specification with the engine at 1250 RPM. One trip fault.
Possible Causes |
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| ENGINE OIL/ENGINE MECHANICAL |
| EXCESSIVE RESISTANCE IN THE (G6) ENGINE OIL PRESSURE SENSOR SIGNAL CIRCUIT |
| EXCESSIVE RESISTANCE IN THE (F855) 5 VOLT SUPPLY CIRCUIT |
| EXCESSIVE RESISTANCE IN THE (K900) SENSOR RETURN CIRCUIT |
| ENGINE OIL PRESSURE SENSOR |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
1. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
| NOTE: | Make sure that the engine oil is at the proper level. Also, review the customers oil change history to ensure that the oil is being changed at the correct intervals and that the proper oil viscosity is being used. |
| 1. | Start the engine and allow it to reach normal operating temperature. |
When the engine is operating, do
not stand in direct line with the fan. Do not put your hands near
the pulleys, belts or fan. Do not wear loose clothing. Failure to
follow these instructions may result in possible serious or fatal
injury.
WARNING:
| 2. | Using the scan tool, read the active DTCs. |
Is the DTC Active at this time?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
2. ENGINE OIL/ENGINE MECHANICAL
| NOTE: | The following items should be considered before determining the cause of this DTC. Failure to do so may lead to misdiagnosis. |
| 1. | If any of the above conditions are found, repair as necessary. |
Were any of the above conditions present?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Go To 3
 |
| 1. | Turn the ignition off. |
| 2. | Disconnect the Engine Oil Pressure Sensor harness connector. |
| 3. | Ignition on, engine not running. |
| 4. | With the scan tool, monitor the Engine Oil Pressure Sensor voltage. |
| 5. | Connect a jumper wire between the (K900) Sensor Ground circuit and the (G6) Engine Oil Pressure Signal circuit. |
| NOTE: | Engine Oil Pressure voltage should change from approximately 4.5 volts to less than 0.5 volt. |
Is the voltage reading within the listed specification when the jumper wire is installed?
Yes
- Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors. Remove the Engine Oil Pressure sensor and ensure the oil passage/port is free from any blockage. If OK, replace the Engine Oil Pressure Sensor. (Refer to 09 - Engine/Lubrication/SENSOR, Oil Pressure - Removal) .
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
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Go To 4
NOTE: Remove the jumper wire before continuing.
4. EXCESSIVE RESISTANCE IN THE (G6) ENGINE OIL PRESSURE SIGNAL CIRCUIT
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| 1. | Turn the ignition off. |
| 2. | Disconnect the PCM C2 harness connector. |
| 3. | Measure the resistance of the (G6) Engine Oil Pressure Signal circuit from the Engine Oil Pressure Sensor harness connector to the PCM C2 harness connector. |
Is the resistance below 5.0 Ohms?
Yes
- Go To 5
No
- Repair the excessive resistance or open in the (G6) Engine Oil Pressure Signal circuit.
-
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM)
- Standard Procedure).
5. EXCESSIVE RESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT
 |
| 1. | Measure the resistance of the (F855) 5-Volt Supply circuit from the Engine Oil Pressure Sensor harness connector to the PCM C2 harness connector. |
Is the resistance below 5.0 Ohms?
Yes
- Go To 6
No
- Repair the excessive resistance in the (F855) 5-Volt Supply circuit.
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Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM)
- Standard Procedure).
6. EXCESSIVE RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT
 |
| 1. | Measure the resistance of the (K900) Sensor Ground circuit from the Engine Oil Pressure Sensor harness connector to the PCM C2 harness connector. |
Is the resistance below 5.0 Ohms?
Yes
- Go To 7
No
- Repair the excessive resistance in the (K900) Sensor Ground circuit.
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Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM)
- Standard Procedure).
7. POWERTRAIN CONTROL MODULE (PCM)
| 1. | Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Oil Pressure Sensor and the Powertrain Control Module (PCM). |
| 2. | Look for any chafed, pierced, pinched or partially broken wires. |
| 3. | Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors. |
| 4. | Perform any Technical Service Bulletins that may apply. |
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Replace and program the Powertrain Control Module in accordance with the service information. (Refer to 08 - Electrical/8E - Electronic Control Modules/MODULE, Powertrain Control - Removal) .
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).