P0636Power Steering Control Circuit Low
- Generic OBD-II code · Powertrain
- Can trigger limp mode
- How the car detects it
- P0635–P0637 concern the control or signal circuit between engine module and power steering – depending on the maker the drive of an electro-hydraulic pump or the steering load signal the engine module uses to raise idle. CARB requires power steering components to be monitored only if another diagnostic uses them, so these codes are rare and maker-specific. Mercedes-Benz stores P0635 in the electric steering module itself (no assist after start, software update); no engine module table available to us uses P0635–P0637. P0636 means the voltage in this circuit is too low – the wire is shorted to ground, supply voltage is low, or the driver sees a low state although it commanded 'on'. No manufacturer threshold is published.
- What you may notice
- Power steering warning, heavy steering
- Check engine light (depending on the maker)
- Idle drops when steering
- Likely causes
- LikelySignal or control wire shorted to ground (chafing)
- PossibleUndervoltage from battery, alternator or ground
- PossibleSteering module or pump module faulty internally
- RareEngine module driver faulty
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.