Is a power steering warning light an MOT failure?

Yes. An electronic power steering malfunction indicator lamp that shows a system fault is a major defect, and so is assistance that is not working at all. Nothing is mechanically loose and the car still drives, but the tester is entitled to treat the vehicle's own diagnosis as evidence of a fault. A bulb check that clears normally after starting is not this defect.

Can I still drive with no power steering?

The car remains steerable, but the effort at low speed is far higher than most drivers expect, and assistance tends to disappear at the least convenient moment — mid-manoeuvre, or on the first lock at a busy junction. Some systems reduce assistance progressively as a fault develops rather than switching off cleanly, which makes the car's responses inconsistent.

Why does my power steering come back after I restart the car?

An intermittent fault points at the electrical side rather than anything mechanical: a corroded connector, a poor earth, a marginal supply voltage, or a stored fault elsewhere, since many electric racks withdraw assistance when they lose a wheel speed signal from ABS. Clearing the code and hoping rarely works, and it destroys the freeze-frame data a garage needs.

Can a weak battery cause a power steering fault?

It can. Electric assistance draws heavily under load, so a tired battery, a dirty terminal or a poor earth is enough to trigger an assistance fault on plenty of cars. Battery condition and terminal cleanliness are among the few things genuinely worth checking yourself before paying for anything further, along with connectors under the column and in the wheel arch.

How much does it cost to fix an electric power steering fault?

Budget £60 to £120 for diagnostic time first, because the repairs behind one lamp range from trivial to enormous. A corroded earth, a connector repair or a new battery is £70 to £200. Sensors and modules that can be replaced separately are £200 to £450 including coding. A complete column or rack assembly is £500 to £850 fitted on a mainstream car.

MOT defect file

Power steering warning lamp on, or assistance not working

Last updated 27 July 2026

Quick answer

The steering system is reporting its own fault, or the assistance has dropped out. The car remains steerable but takes far more effort, particularly when parking, and an illuminated steering warning lamp is a failure in itself.

Typical cost: £70–£850
DIY viability: Garage job

A testable malfunction indicator that stays illuminated with the engine running records a system fault. The exact symbol varies by vehicle, but ABS, SRS, electronic power steering, ESC, engine management, brake-system and tyre-pressure warnings must not be ignored.

What you might notice

A steering-shaped warning symbol lit on the dashboard, often amber with an exclamation mark beside a steering wheel
Assistance disappearing suddenly, so the wheel becomes very heavy — most obvious at parking speeds and barely noticeable on a motorway
Assistance that comes and goes, typically returning after the ignition is switched off and on again
Uneven effort, where the wheel is light in one direction and heavy in the other, which points at the motor or torque sensor rather than the wiring

What causes it

A failing torque or steering angle sensor in the column, which is what the system uses to decide how much help to give
A worn or water-damaged column motor, most often on cars where the electrical connector sits low and has taken road spray
Voltage supply problems — a tired battery, a poor earth, or a corroded high-current connector — since electric assistance draws heavily under load
A stored fault from another system, because many electric racks reduce or withdraw assistance when they lose a wheel speed signal from ABS

Advisory or failure?

An electronic power steering malfunction indicator lamp that shows a system fault is a major defect and a failure, and so is a power steering system that is not working at all. The point catches people out because nothing is mechanically loose and the car drives, but the tester is entitled to treat the vehicle's own diagnosis as evidence of a fault. Related items are graded alongside it: a steering component or wiring that is insecure or damaged is a major defect, and where the fault could result in the loss of steering control the grading is dangerous. A lamp that is on for a different system, or a bulb check that clears normally after starting, is not this defect — a warning lamp indicating a steering fault only fails the car where it stays lit to report one.

Can you fix it yourself?

Garage job

Read the fault codes before touching anything, because the range of causes behind one lamp is enormous and guessing here is expensive. A basic code reader may not reach the steering module at all — many need a manufacturer-level tool — which is why a diagnostic session is the sensible first spend. There are two things worth checking yourself: battery condition and terminal cleanliness, since low voltage alone triggers assistance faults on plenty of cars, and any exposed connector under the column or in the front wheel arch for corrosion or water. Do not clear the code and hope; on most systems the lamp will simply return, and clearing it before diagnosis destroys the freeze-frame data the garage needs.

What it costs

Budget £60 to £120 for diagnostic time first; it is the most useful money you will spend, because the repairs behind this lamp range from trivial to enormous. At the bottom, a corroded earth, a connector repair or a new battery is £70 to £200. In the middle sit sensors and control modules that can be replaced separately, £200 to £450 including coding. At the top, a complete electric power steering column or rack assembly is £500 to £850 fitted on a mainstream car, and more on a premium model, since the unit usually has to be coded to the vehicle and the steering angle sensor recalibrated. Ask whether a specialist rebuild of your existing unit is an option — it is often half the price of a new assembly.

What happens if you ignore it

Losing assistance does not leave you unable to steer, but the effort at low speed is far higher than most drivers expect, and it usually goes at the least convenient moment — mid-manoeuvre, or on the first lock of a busy junction. Some systems also progressively reduce assistance as a fault develops rather than switching it off cleanly, which makes the car's responses inconsistent. Beyond the driving, it is a straight failure, so the car cannot be legally used once the certificate expires, and an intermittent electrical fault left alone tends to become a permanent one — often after water has had a few more months to work on a connector that could have been cleaned and sealed.

Common questions

Is a power steering warning light an MOT failure?: Yes. An electronic power steering malfunction indicator lamp that shows a system fault is a major defect, and so is assistance that is not working at all. Nothing is mechanically loose and the car still drives, but the tester is entitled to treat the vehicle's own diagnosis as evidence of a fault. A bulb check that clears normally after starting is not this defect.
Can I still drive with no power steering?: The car remains steerable, but the effort at low speed is far higher than most drivers expect, and assistance tends to disappear at the least convenient moment — mid-manoeuvre, or on the first lock at a busy junction. Some systems reduce assistance progressively as a fault develops rather than switching off cleanly, which makes the car's responses inconsistent.
Why does my power steering come back after I restart the car?: An intermittent fault points at the electrical side rather than anything mechanical: a corroded connector, a poor earth, a marginal supply voltage, or a stored fault elsewhere, since many electric racks withdraw assistance when they lose a wheel speed signal from ABS. Clearing the code and hoping rarely works, and it destroys the freeze-frame data a garage needs.
Can a weak battery cause a power steering fault?: It can. Electric assistance draws heavily under load, so a tired battery, a dirty terminal or a poor earth is enough to trigger an assistance fault on plenty of cars. Battery condition and terminal cleanliness are among the few things genuinely worth checking yourself before paying for anything further, along with connectors under the column and in the wheel arch.
How much does it cost to fix an electric power steering fault?: Budget £60 to £120 for diagnostic time first, because the repairs behind one lamp range from trivial to enormous. A corroded earth, a connector repair or a new battery is £70 to £200. Sensors and modules that can be replaced separately are £200 to £450 including coding. A complete column or rack assembly is £500 to £850 fitted on a mainstream car.

The warning light behind this

This defect is what a tester writes down. What you see from the driver’s seat is a symbol, and it is worth checking which one, because manufacturers reuse the same shape for more than one system.

Power steering warning lightWhat it means and whether you can keep driving

Fault codes behind this failure

A failure certificate records that the lamp was lit, not what lit it. If this is what your certificate says, one of these codes is usually stored behind it, and reading it is the difference between a diagnosis and a guess.

This is general guidance, not a diagnosis. The severity DVSA records depends on the specific fault found, so the same item can appear as an advisory on one test and a failure on another. Ask a qualified tester or mechanic to inspect the vehicle.

Has this been recorded on your car?

Check the full MOT history for any UK registration.