Chevy S10P0523: Meanings and Causes. + Most Likely Fixes

The OBD2 standard trouble code P0523 can be found in Chevy S10. In layman’s terms, it indicates the signal from the oil pressure sensor is higher than its normal operating range (in terms of voltage).

P0523 is generic (it has the same definition for all vehicles), repair steps will depend on your S10’s model year and the engine equipped.

The most frequent cause of P0523 is a bad oil pressure sensor. But, this could be caused by an oil system fault. Don’t assume the sensor is bad until you confirm the oil pressure manually. If there’s an oiling issue, it can cause engine damage or failure.

P0523 Definition: Engine Oil Pressure Sensor/Switch – High Input

Here’s precisely what P0523 is telling you:

Oil Pressure Sensor/Switch

The oil pressure sensor bolts into your S10’s engine and relays the oil pressure reading to the Powertrain Control Module (PCM). This converts the mechanical pressure reading to a voltage value which the PCM can understand.

The PCM sends the oil pressure to the oil gauge (or the warning light) from the PCM.

High-Input

A voltage value that is nearly at its highest value or greater (which indicates to the PCM that oil pressure levels are very high) is called P0522. If the input was low, you’d have P0522.

Chevy S10 P0523 Symptoms

Your S10 may feel like it’s running and driving fine, but even without symptoms, you shouldn’t drive it with P0523 until you verify the oil pressure is fine.

These are some of the symptoms that most commonly occur with P0523.

• Check engine light
• A high reading of the gauge's oil pressure, or the light that indicates it could be on, can indicate excessive oil pressure.

P0523 Causes of the Chevy S10

There are two things going on. One, the oil pressure may be too high or the sensor is malfunctioning.

These are some of the more common reasons for P0523 in Chevy S10, and how to identify them.

Examine the oil

Verify that the oil level isn’t overly full. Does it feel sluggish? What is the correct weight of it? If you didn’t pour it in yourself, it’s possible that the wrong viscosity was used the last time the oil was changed. If you get P0523 immediately after an oil-change, this is a possibility.

Bad Oil Pressure Sensor – Wiring

If the oil level is correct, it’s not old, and it’s the proper viscosity, it’s time to look at your S10’s oil pressure sensor. These sensors are close to the exhaust and can lead to widespread wiring problems.

Examine the harness carefully for obvious damages. Look for cracked, broken, burnt, or brittle wiring. You should follow the wiring as closely as possible, however you must be within two feet of the plug.

The Oil Pressure Sensor can be tested

A simple multimeter can be used to test the oil pressure sensor/switch. You can see how it works for almost every oil pressure sensor in the video.

Another option is to purchase a mechanical oil tester at a Harbor Freight or AutoZone. They’re usually around $25-$40 and will 100% tell you if you have a real oil pressure problem. That’s about the same price as a new oil pressure sensor, and you’ll be plugging into the same hole anyway.

If the manual oil pressure checks out, you have positive proof that your S10 doesn’t have a sensor or wiring issue.

Problems with mechanical components

While a bad oil pressure sensor or wiring issue is the most common cause of P0523, it’s not the only one. The code may also be caused by an oil pump problem or restricted oil flow in your S10. You can verify this with an oil pressure test kit (it’s just a mechanical oil gauge with adapters to fit most makes/models).

Conclusion

There are several things that could cause P0523 to the Chevy S10. Check the oil, and test the oil pressure sensor. More often than not, that’ll fix the code. Have fun!