MOT defect file
Direction indicator not working
Last updated
Quick answer
One of the indicators is not operating, or is flashing at the wrong rate. Usually a bulb or a corroded holder, and one of the cheapest failures to put right.
- Typical cost
- £5–£60
- DIY viability
- Straightforward
What you might notice
- The tell-tale on the dashboard flashes roughly twice as fast as normal
- A corner of the car stays dark when you signal, easiest to check against a window or garage door at night
- Indicators work intermittently, or only once the lamp has warmed up
- Nothing obvious from the driver's seat — most people find out at the test
What causes it
- A blown filament bulb, which is by far the most common cause
- Corrosion in the bulb holder or a poor earth, giving intermittent contact
- Water ingress into the lamp unit through a perished seal
- A failed LED cluster, which on many modern cars cannot be repaired separately from the unit
Advisory or failure?
An indicator that does not work, is missing, or flashes outside the permitted rate of 60 to 120 times per minute is a major defect and a failure. A lens that is cracked but still shows the correct colour and intensity is usually a minor defect. Incorrect colour, or a lamp so dim or obscured that it is not clearly visible, is also a major defect.
Can you fix it yourself?
Straightforward
On most cars a front indicator bulb is reachable through the wheel arch liner or from behind the headlamp unit, and a repeater is a twist-and-pull. Buy the right bulb type, handle it with a cloth so skin oils do not shorten its life, and check the holder for green corrosion while you are in there. LED units are the exception: if the cluster has failed, replacement is the only option and it is a garage-priced part.
What it costs
A bulb is a few pounds and ten minutes of your own time. A garage will charge a half-hour of labour on top, so £20 to £40 all in. Where the fault is a corroded holder or a wiring repair, expect £40 to £70. A sealed LED unit is the outlier and can run well beyond this band, so it is worth confirming which type you have before agreeing to work.
What happens if you ignore it
Beyond the certain MOT failure, a car that cannot signal properly is genuinely dangerous at junctions and roundabouts, and it invites blame in any collision where your intentions were disputed. It is also an offence to use a vehicle with defective lighting on a public road, so it is an easy roadside stop.
Common questions
- Is a broken indicator an MOT failure?
- Yes. An indicator that does not work, is missing, or flashes outside the permitted range of 60 to 120 times a minute is a major defect, which means the vehicle fails. A cracked lens that still shows the correct colour and brightness is usually recorded as a minor defect instead, so the car can still pass with it noted.
- Why is my indicator flashing twice as fast as normal?
- A rapid flash is the car telling you a bulb in that circuit has failed. The flasher relay senses the reduced electrical load and speeds up deliberately, because you cannot see the dead lamp from the driver's seat. Walk round the car with the indicator on and you will find the one that is out.
- How much does it cost to fix an indicator?
- A filament bulb costs a few pounds and takes about ten minutes, so doing it yourself is close to free. A garage will typically charge £20 to £40 including labour, or £40 to £70 if the holder is corroded and needs cleaning or replacing. A sealed LED unit is the expensive case and can cost considerably more, because the whole lamp assembly has to be replaced.
- Can I drive with a broken indicator?
- You should not. Using a vehicle with defective lighting on a public road is an offence, and an indicator that does not work is genuinely dangerous at junctions and roundabouts because other drivers cannot read your intentions. It is also one of the easiest faults for a police officer to spot.
- Can I change an indicator bulb myself?
- Usually yes. Most front indicators are reachable through the wheel arch liner or from behind the headlamp unit, and side repeaters are often a simple twist and pull. Buy the correct bulb type, handle the glass with a cloth so skin oils do not shorten its life, and check the holder for green corrosion while you have it apart.
Cars this happens to most
Of every model with at least 2,000 tests in the DVSA data, these record direction indicator not working on the largest share of their MOTs. Across all of them the typical rate is 0.6% of tests.
- Talbot Express7.6%
367 times in 4,826 tests
- Citroen 2CV4.6%
113 times in 2,466 tests
171 times in 4,737 tests
- Saab 9003.5%
74 times in 2,115 tests
847 times in 24,505 tests
160 times in 4,999 tests
- Volkswagen LT3.1%
76 times in 2,480 tests
- Jeep Wrangler2.7%
192 times in 7,080 tests
A high rate here is a property of the fleet as much as the car: these models skew old, and almost everything fails more with age. It is a reason to check the item on a used example, not proof the model is badly built. Models with fewer than 2,000 tests are left out because a rate drawn from a few hundred cars moves too much to rank.
Warning lights 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.
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.