P0635
Power Steering Control Circuit
A general circuit fault is detected on the power steering control output - typically the line that the ECU uses to request raised idle when steering load is high, or to enable an electric pump.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Common causes
Ordered by how often each turns out to be the cause.
- Open in control lineCommon
Parts involved
- Power Steering Control Signal
P0635 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.