Subaru BRZ P0523 - Meanings, Causes, and + Likely Fixes

A standard OBD2 code, P0523 can be found in Subaru BRZ. 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 BRZ’s model year and the engine equipped.

The most frequent cause of P0523 is a bad oil pressure sensor. This code could also be triggered by an oil system problem. 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 BRZ’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 transmits oil pressure from the PCM to the oil-pressure gauge (or warning lamp).

High input

This indicates that the voltage value is close to or higher than its maximum value. It also tells the PCM the oil pressure is high. If the input was low, you’d have P0522.

Subaru BRZ Symptoms P0523

Your BRZ 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
• The gauge could show high oil pressure or an oil pressure light.

Subaru BRZ Causes

It could be one of two issues. There are two possible causes.

These are some of the more common reasons for P0523 in Subaru BRZ. We also have the correct order to inspect them.

Take a look at 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. This is what you should do if P0523 appears right after an oil change.

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 BRZ’s oil pressure sensor. Due to their close proximity to exhaust, wiring issues are common with these sensors.

Check the harness for damage. Look for cracked, broken, burnt, or brittle wiring. The harness should be followed as far as you are able, with a particular focus on the area where it connects to the head.

Check the oil pressure sensor

With a multimeter, you can easily test the oil-pressure switch or sensor. 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 BRZ 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. This code can be caused by a faulty or blocked oil passageway in your BRZ. 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 a few things that could cause P0523 to the Subaru BRZ. Check the oil, and test the oil pressure sensor. More often than not, that’ll fix the code. You are welcome!