P0636 Power steering control circuit: signal or voltage too low

By: Diagno editorial team · Updated: 2026-10-15

P0636 means: Power steering control circuit: signal or voltage too low. The steering or chassis system (steering angle sensor, electric power steering, suspension, brakes) found a fault. Drive gently and have the car checked soon. The most common repair costs about €45–90 in Estonia, depending on make and model.

What it means

The steering or chassis system (steering angle sensor, electric power steering, suspension, brakes) found a fault. The signal voltage is too low. Usually a wire is broken, a connector is loose or a wire is shorted to ground.

What you may notice

• Warning light on
• Steering may be heavy
• ESP may be switched off

What could be wrong

1. 1Connector loose, damp or corroded · Wiring or connector repair €45–90
2. 2Wire broken or shorted to ground · Wiring or connector repair €45–90
3. 3Faulty sensor or steering unit · Sensor replacement €80–160
4. 4Engine computer fault (rare) · Control unit check and software €150–300

Repair difficulty: Moderate

What you can check yourself

First look at the connector and wiring: anything loose, melted or green with corrosion? If the steering is heavy, drive carefully. After tyre or alignment work the steering angle sensor often needs recalibrating. Best left to a workshop. It needs a diagnostic tool and experience.

How we fix it

1. We read the fault data on the diagnostic tool and check whether the fault is constant
2. We measure the circuit's supply, ground and signal
3. We repair the wire or replace the connector
4. If the wiring is fine, we replace the sensor or steering unit

Standard SAE description: Power Steering Control Circuit Low