Error Code P0522 is defined as Engine Oil Pressure Sensor/Switch Low Voltage. This means the sensor is indicating that the oil pressure value is too low, which is due to faulty sensor, faulty sensor circuit or low oil level.

This code is a generic trouble code, meaning it applies to all vehicles equipped with the OBD-II system, especially vehicles made since 1996 up to present.  Specifications on the definition, troubleshooting and repairs vary depending on the vehicle makes and/or models.

This error code applies to all vehicles makes and models, but is more common among Buick, Cadillac, Chevrolet, Dodge, GMC brands.

Definition

The PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes) is the main computer of the vehicle. It takes control of many electronics, sensors and controls within the vehicle, especially the engine. One of these sensors that the PCM controls is the oil pressure sensor or sender, and it detects the amount of oil pressure (mechanical) in the engine, relaying that information in the form of voltage reading/value to the PCM. For some vehicles, the oil pressure value is then relayed to a gauge into the instrument cluster to show oil pressure to the driver. Other times, the gauge is not there, but there will be a warning light should there be a problem.

Error Code P0522 is triggered when the PCM has detected a voltage that is lower than normal coming from engine oil pressure sensor. If the engine oil pressure actually drops too low, it can cause permanent damage to the engine. Thus, if you notice this error code, or a low oil pressure condition in your vehicle, it is crucial that you pull over and shut the engine off as soon as possible.

Other trouble codes related to this are P0520, P0521, P0523, and P0524.

Common Symptoms

As with other error codes, this code triggers the Check Engine light and registers the code in the PCM. Other symptoms of Error Code P0522 include:

  • Engine may not start
  • Engine quits or stalls while in the middle of driving
  • Oil pressure gauge reading zero or low
  • Oil pressure indicator lamp illuminated

Possible Causes

There are many possible causes for this error code to appear; which include:

  • Faulty oil pressure sensor
  • Low oil level, blockage in the oil passage way or use of wrong oil
  • Open or short in the sensor circuit wiring
  • Bad connection, faulty connector in the oil pressure sensor circuit

How to Check

Technicians diagnose this code by clearing the codes first and then take the vehicle for a test drive. They will observe the live scanner data to see if the code returns.

Then, they will check the oil level and condition.

They make sure the vehicle is using the correct oil and that the filter is not being blocked or clogged.

Then they inspect the oil pressure sensor or sender unit’s wiring and connectors and look for signs of damages, burned areas, loose connections or wires, etc.

Next, they will use an ohmmeter (DVOM or digital volt-ohmmeter) to test the oil pressure sensor and make sure its voltage matches the specifications set by the vehicle’s manufacturer.

Then, they check the oil pressure using a mechanical oil pressure gauge, and compare that reading to the sensor readings.

How to Fix

As said earlier, Error Code P0522 must be addressed as soon as possible, as it can cause major mechanical problems, which can even be more expensive to fix in the long term.

For repairs:

  • Check all concerned wirings and connectors and look for signs of damages, burned spots, disconnected wires, corrosion, etc., and repair or replace as necessary
  • Replace oil pressure sensor if it doesn’t test at correct voltage
  • Repair any damages caused by actual low oil pressure

Failure to turn off the engine during low oil pressure situation will cause engine noise, and possibly even engine failure, which is usually catastrophic.

Also, note that there is a known service bulletin to 2005-2010 vehicles, including the usual makes that gets this code, such as Buick, Cadillac, Chevrolet, Pontiac, and Saab, which is Bulletin number PIP4786. Make sure you check your vehicle if it requires a specific diagnosis.

Fortunately, this code almost always reflects faulty electrical or sensor (or sender) unit, and as soon as the problem is fixed, and the problem in the low oil gauge indicator is fixed, the code will be fixed.

Also, check your oil and have it changed regularly to avoid this problem.