P0637

Power Steering Control Circuit High

Q: Is it safe to drive with P0637?

It's driveable, but assist may drop out, making the wheel heavy — get it fixed soon, particularly if you rely on it for parking and slow turns.

Q: Can I just clear P0637?

It returns until the open or shorted control circuit is repaired.

Power steering control Generic OBD-II Medium

What it means

P0637 means the power-steering control circuit is reading a high voltage — usually an open or a short to power in the circuit the computer uses to command steering assist. Depending on the system, power-steering assist may be reduced or drop out. The engine still starts and runs normally.

Medium

Can I keep driving? Steering still works, but assist may be reduced or inconsistent so effort can increase — get it fixed soon, especially for low-speed maneuvering and parking.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Reduced, heavy, or inconsistent power-steering assist
Power-steering or check-engine warning light on
Steering effort that changes or feels jerky
Unusual noise from the power-steering system on some vehicles

Common causes

Most likely first

Open circuit or short to power in the power-steering control wiringLikely
Corroded or loose connector at the power-steering control module or actuatorCommon
Faulty power-steering control moduleCommon
Low system voltage (weak battery or alternator) on electric-assist systemsLess often

How to diagnose & fix

Work through it in order

Read freeze-frame data and scan for other power-steering codes.
Inspect the control wiring and connector for opens and shorts to power.
Verify system supply voltage and ground integrity.
Test the control module's command signal to the steering actuator.
Replace the module or actuator only if the wiring and supply check good.

FAQ

Quick answers

Is it safe to drive with P0637?+

It's driveable, but assist may drop out, making the wheel heavy — get it fixed soon, particularly if you rely on it for parking and slow turns.

Can I just clear P0637?+

It returns until the open or shorted control circuit is repaired.

Read & clear P0637 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX