Technical Description of OBD-II Trouble Code
Generic: High Engine Oil Pressure Sensor/Switch
Chrysler: High Input Conditions for Oil Pressure Sensor
GM: High Input Conditions for Engine Oil Pressure Sensor Circuit
This diagnostic trouble code (DTC) is a generic OBD-II powertrain code. It is considered generic because it applies to all makes and models of vehicles (1996-newer), although specific repair steps may vary depending on the model. In our experience, the P0523 engine code appears more frequently on Chevrolet, Jeep, GMC, Dodge, Honda, and Cadillac, but it applies to any make/model.
What does that mean?
The Powertrain Control Module (PCM), the vehicle’s main computer, controls many sensors, controls, and electronics in the vehicle. One of these sensors, called the oil pressure sensor or sender, detects the mechanical oil pressure in the engine and relays it to the PCM as a voltage reading/value. In some vehicles, this oil pressure value is then displayed on a gauge in the instrument cluster to show the driver the oil pressure. In other vehicles, there may be a warning light instead of a gauge.
This specific P0523 engine code is triggered when the PCM detects a value that is too high in the engine oil pressure sender/sensor. The oil pressure sensor operates on a 5-volt circuit. Generally, this engine code is triggered when the voltage is 4.6 or higher. The cause of this trouble code may be mechanical or electrical, but it is most likely related to an electrical issue. This code is related to other oil pressure DTCs: P0520, P0521, P0522, and P0524.
Symptoms
Symptoms of a P0523 DTC may include:
Causes
Potential causes of a P0523 code include:
Diagnostic & Repair Steps
Before proceeding with diagnostics, it is advisable to check for any technical service bulletins (TSBs) that may apply to your vehicle.
As a vehicle owner or DIYer, the first step is to check the oil level using the dipstick. Ensure that the engine has the correct type and weight of oil and that it is not old, thick, or sludged up.
Next, visually inspect the wiring and connectors at the oil pressure sending unit. Look for any broken or frayed wires, burnt spots, loose or exposed wiring, etc. Consult a model-specific resource to locate the sender.
A technician may start by performing a mechanical oil pressure test using a mechanical gauge and compare the reading with the value of the sensor as read by the PCM. An advanced scan tool is required for this. If the sensor or wiring is faulty, the mechanical gauge test will immediately indicate that. If you are performing the job yourself, this is the next step.
If it has been determined that there is no actual problem with the oil pressure, the issue lies either within the sensor or the wiring/connectors.
Use a digital volt ohm meter (DVOM) to check the sensor itself. If it does not meet the manufacturer’s specifications, it should be replaced. Also, check the voltage going to the oil pressure sensor to ensure it is receiving 5 volts. Replacing the sensor/sender or addressing any wiring issues is the most likely repair for this code. If everything checks out, test the wiring and connectors from the sensor to the PCM. Verify that there are no breaks in the wiring due to chafing, pinching, etc. Ensure that the electrical connectors are tight and free of corrosion.
P0523 Diagnostic Repair Video
We found a video that could be helpful if you have a P0523 engine code. Please note that we are not affiliated with the producers of this video:
As you can see, there are several possible reasons for the P0523 code. If the sending unit is inexpensive, you could try replacing it first to see if that resolves the issue. However, a proper diagnosis is highly recommended to avoid replacing perfectly good parts. Good luck, and if you need assistance, feel free to visit our forum.
