P0521-Engine Oil Sensor Quality Performance: Notes
- When Monitored : With the engine running.
- Set Condition
: Anytime the Powertrain Control Module (PCM) senses the Oil Quality value is above 4.0.NOTE: The engine oil must be changed before this test can be accurately conducted.
| Possible Causes |
| WATER IN THE OIL |
| CONTAMINATED OIL |
| OIL SENSOR SIGNAL CIRCUIT OPEN |
| OIL SENSOR SIGNAL CIRCUIT SHORT TO GROUND |
| OIL SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE |
| 5-VOLT SUPPLY CIRCUIT OPEN |
| 5-VOLT SUPPLY CIRCUIT SHORT TO GROUND |
| 5-VOLT SUPPLY CIRCUIT SHORT TO VOLTAGE |
| 5-VOLT SUPPLY CIRCUIT SHORT TO SENSOR GROUND CIRCUIT |
| OIL SENSOR SIGNAL CIRCUIT SHORT TO SENSOR GROUND CIRCUIT |
| OIL SENSOR SIGNAL CIRCUIT SHORT TO 5-VOLT SUPPLY CIRCUIT |
| SENSOR GROUND CIRCUIT OPEN |
| MANIFOLD ABSOLUTE PRESSURE SENSOR |
| ENGINE OIL SENSOR |
| POWERTRAIN CONTROL MODULE |
For a complete Powertrain Control Module Circuit Diagram, refer to SCHEMATICS AND DIAGRAMS .