Why is my traction control light flashing?

Because the system is working. A flash means a driven wheel has started to spin faster than the others and the car is cutting engine torque, braking that wheel, or both, to get the grip back. It is normal on wet roads, painted markings, manhole covers, gravel and cold mornings. Ease off the accelerator and it will stop. Only a steady, permanently lit lamp indicates a fault.

Does the traction control light fail an MOT?

Traction control by itself is not tested, so there is no defect for the lamp. But most cars use the same skidding-car symbol for traction control, stability control and the stability control malfunction lamp — and a stability control malfunction lamp is a major defect under section 7.12, with 35,322 failures recorded in the DVSA data behind this site. If yours is on steadily, find out from the handbook which system the symbol belongs to before assuming it will pass.

Is it safe to drive with the traction control light on?

Yes, in the sense that nothing will fail and the car handles normally. If the lamp is steady the system is unavailable, so a driven wheel can spin up when pulling away on a wet or icy surface and the car will not intervene. Drive with more care in poor conditions and get it diagnosed, particularly through winter. If it is flashing rather than steady, there is nothing wrong at all.

What is the difference between traction control and stability control?

Traction control stops a driven wheel spinning when you accelerate — it works in a straight line and only on the driven wheels. Stability control is broader: it compares where you are steering with where the car is actually going, and brakes individual wheels, including undriven ones, to pull the car back into line when it starts to understeer or oversteer. Stability control is the MOT-tested one; traction control is not.

Dashboard warning light

Traction control light

Last updated 27 July 2026

Quick answer

Flashing, it means the system is doing its job right now — a wheel has started to spin and the car is cutting power or braking it to get grip back. Staying on steadily is the opposite: it means the system has switched itself off and needs looking at.

What to do: No action needed
Can you drive?: Yes

Why it is amber

A system has reported a malfunction, or something needs attention. The car is usually still driveable, but the fault will not clear itself and several amber lamps are an automatic MOT failure.

What turns it on

Traction control watches for one driven wheel turning faster than the others, which means it has lost grip. It responds by trimming the engine's torque and braking that wheel until it matches, and flashes the lamp while it does so. The same lamp is used steady, without flashing, to report that the system has disabled itself after a fault — on many cars it is the same symbol used for stability control, because they are two functions of one module.

What to do about it

If it flashes briefly when pulling away in the wet, on a painted road marking, or on a cold morning, do nothing. Ease off the accelerator and let it work. That is the system operating exactly as designed.
If it flashes constantly on a dry road at steady speed, look at your tyres. Persistent intervention where there should be plenty of grip usually means one tyre is worn, underinflated, or a different size from the rest.
If it is on steadily rather than flashing, treat it as a fault and get the codes read. A permanently lit lamp means the function is unavailable, not that it is working.
Check whether the ABS lamp is on too. Traction control depends on the same wheel speed sensors, and the pair together points at one sensor.
Check the handbook to find out what your car uses this symbol for. On a lot of cars one skidding-car symbol covers traction control, stability control and the ESC malfunction lamp, and that distinction is the difference between an MOT pass and a major defect.

Can you keep driving?

Yes

A flashing lamp means the car is actively helping you and there is nothing to fix. A steady lamp means you are driving without traction control, which changes nothing in normal conditions but will let a driven wheel spin up on a wet or icy pull-away. Neither stops you driving. What matters is establishing which of the two you have, because on many cars a steady lamp is also the stability control malfunction lamp, and that one is a major MOT defect.

What causes it

Normal operation on a slippery surface, which is the flashing case and not a fault at all
A worn, underinflated or mismatched tyre making one wheel spin more readily than the others
A failed wheel speed sensor or damaged reluctor ring, which is the usual cause of a steady lamp
A steering angle or yaw sensor fault on cars where the two systems share a module
The system switched off deliberately, on cars that use this lamp for that too
A brake light switch fault, which some systems treat as a required input

Does it fail an MOT?

No.

Traction control on its own is not an MOT item: there is no defect for the lamp, and no requirement for the system to be present or working. The catch is the symbol. Most manufacturers use one skidding-car icon for traction control, stability control and the stability control malfunction lamp, and the last of those is a major defect. A tester seeing a steady lamp has to work out which system it belongs to, and the manual tells them to consult the handbook if they are not certain. A flashing lamp is the system operating and is never a defect.

Fault codes that turn this light on

The lamp tells you which system reported a problem. The code stored behind it names the check that failed, which is the difference between knowing something is wrong and knowing where to look. These are the ones that commonly sit behind this symbol.

C0035 Front left wheel speed sensor not reading
C0040Right Front Wheel Speed Sensor Circuit Malfunction
C0045 Rear left wheel speed sensor not reading
C0050Right Rear Wheel Speed Sensor Circuit Malfunction

Got a different code? Look it up — the index covers every standard OBD-II code.

Common questions

Why is my traction control light flashing?: Because the system is working. A flash means a driven wheel has started to spin faster than the others and the car is cutting engine torque, braking that wheel, or both, to get the grip back. It is normal on wet roads, painted markings, manhole covers, gravel and cold mornings. Ease off the accelerator and it will stop. Only a steady, permanently lit lamp indicates a fault.
Does the traction control light fail an MOT?: Traction control by itself is not tested, so there is no defect for the lamp. But most cars use the same skidding-car symbol for traction control, stability control and the stability control malfunction lamp — and a stability control malfunction lamp is a major defect under section 7.12, with 35,322 failures recorded in the DVSA data behind this site. If yours is on steadily, find out from the handbook which system the symbol belongs to before assuming it will pass.
Is it safe to drive with the traction control light on?: Yes, in the sense that nothing will fail and the car handles normally. If the lamp is steady the system is unavailable, so a driven wheel can spin up when pulling away on a wet or icy surface and the car will not intervene. Drive with more care in poor conditions and get it diagnosed, particularly through winter. If it is flashing rather than steady, there is nothing wrong at all.
What is the difference between traction control and stability control?: Traction control stops a driven wheel spinning when you accelerate — it works in a straight line and only on the driven wheels. Stability control is broader: it compares where you are steering with where the car is actually going, and brakes individual wheels, including undriven ones, to pull the car back into line when it starts to understeer or oversteer. Stability control is the MOT-tested one; traction control is not.

This is general guidance, not a diagnosis. Manufacturers draw the same system differently and reuse symbols for more than one function, so check the handbook for your own car before acting on anything here.

Check what your car has actually failed on

Free MOT history for any UK registration, straight from DVSA records.