You can drive, but do not put it off
The steering has gone heavy
The wheel turns noticeably harder than usual, especially when parking and at low speed. Sometimes the assistance returns after restarting the engine, sometimes it disappears entirely.
You can usually get home or to a garage, but every day of delay adds to the bill.
What to look at in the live data
- System voltage. Electric power steering needs current, and with a weak battery or alternator it shuts down first — that is protection, not a failure.
- Whether there are communication codes for the steering unit: the link is lost more often than the unit fails.
- Steering angle codes — after an alignment or removing the wheel the sensor has to be re-taught its zero.
Common causes, cheapest first
- A weak battery or alternator: the assistance is short of current.
- A corroded earth or the steering unit connector — it lives under the bonnet, in heat and vibration.
- A lost steering angle calibration after someone else's repair. Re-teaching is free.
- The unit overheating after long parking manoeuvres — it shuts down and comes back on its own.
- A failure of the steering unit itself — that one goes to a mechanic.
Codes that show up with this
U0131Lost communication with electric power steeringU0126Lost communication with steering angle sensorC0051Steering angle sensor malfunctionP0561System voltage unstable
These parameters in the reference
Lamps that may be on
Do it step by step
Three voltage readings answer the question of who is to blame: the battery, the alternator or the wiring.How to check the battery and alternator with the app
A symptom is not a diagnosis. The same sign comes from a dozen different causes — the readings are what tell them apart, not the feeling.
How the app helps
CarScan shows exactly these readings live, remembers the highest and the lowest value of the trip, and puts them into a report you can hand to a mechanic.