OBD-II Code P0553 — What It Means & How to Fix It

What Does This Error Mean?

P0553 means the power steering pressure sensor circuit voltage is higher than the maximum valid range. A high-voltage signal typically means the circuit has an open — a disconnected sensor, a broken wire, or a sensor with a failed internal element. When the circuit is open, it floats to the reference voltage and reads as full-scale high pressure. The PCM may react by permanently holding a high idle speed since it believes the power steering pump is always under maximum load.

Affected Models

Vehicles 1996 and newer with hydraulic power steering pressure sensors
Common on GM, Ford, Chrysler, Toyota, Honda, and Nissan
Any vehicle with a belt-driven hydraulic power steering pump connected to the PCM
Higher mileage vehicles with aging wiring harnesses
Vehicles where the power steering pressure sensor has recently been disturbed by engine service

Common Causes

Power steering pressure sensor connector is unplugged or has a disconnected terminal
Sensor wiring has an open circuit — a broken wire between the sensor and the PCM
Sensor internal element has failed open — the coil no longer completes the circuit
Sensor wiring is shorted to battery voltage from contact with a nearby power wire
PCM reference supply voltage is too high due to a regulator fault in the PCM

How to Fix It

Check the power steering pressure sensor connector immediately. The connector may have simply come loose during recent engine work. Locate the sensor on the power steering high-pressure line and reconnect the connector fully.

A disconnected connector is one of the most common causes of high-circuit codes. It is always the first place to look.
Measure resistance across the power steering pressure sensor terminals. An infinite (open) reading confirms the sensor's internal element has failed. Replace the sensor.

Power steering pressure sensors fail open over time from heat and vibration. This is more common on higher mileage vehicles.
Check for battery voltage on the sensor signal wire with the connector unplugged and the ignition on. If you measure 12V on the signal wire, it is shorted to a power source — locate and repair the short before installing a new sensor.

A short to battery voltage on a PCM signal input can cause PCM damage. Always repair the wiring fault before replacing the sensor.
Trace the wiring from the sensor to the PCM for any open circuits. Use a multimeter set to continuity mode and probe along the wire length. An open will show no continuity at the break point.

Focus on the section of harness nearest to the power steering system — this area experiences heat, vibration, and power steering fluid exposure.
Replace the sensor if it reads open. Install snugly and reconnect the electrical connector fully. Start the engine and verify the power steering pressure reading is now in a realistic range on the scan tool live data.

A properly functioning sensor reads low pressure at idle with wheels straight and high pressure when turning against the stops.

When to Call a Professional

P0553 is typically a simple repair — reconnect a connector or replace an open sensor. If there is a wiring short to battery voltage, that needs careful repair to protect the PCM. A shop can diagnose and fix P0553 in under 1 hour in most cases.

Frequently Asked Questions

My car idles too high — could P0553 be the cause?

Yes. If the PCM reads a constantly high power steering pressure signal, it may keep the idle elevated because it thinks the pump is always under heavy load. This manifests as a persistently high idle RPM even when the wheels are straight and no load is on the pump. Fixing P0553 often returns the idle to its normal target speed.

How do I verify the sensor is reading correctly after replacement?

Use a scan tool to view the power steering pressure sensor live data. With the engine idling and the wheels straight, the value should be at or near the low end of the scale. Turn the wheel slowly to full lock — the reading should climb toward maximum. Release the wheel and the reading should drop back down. This confirms the sensor is tracking pressure changes correctly.

Do I need a special wrench to replace the power steering pressure sensor?

Some sensors require a crowfoot wrench or a specialized sensor socket because they are recessed or near obstructions. Many can be removed with a standard 22mm or 27mm wrench or a flare nut wrench. Check the sensor access before starting — some engines have tight clearances around the high-pressure line area.