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Common mistakes made by MOT testers

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MOT sign on garage

We are often asked what are the most common mistakes made by NTs, well here's a few that come up regularly.

1. Daytime Running Lamps (DRLs) and their operation

DLRs are designed to make vehicles more visible during daylight hours and are now common on vehicles of testable age. DRLs themselves are not covered by the manual and are therefore not testable items.

They are fitted to the front of the vehicle only, coming on automatically when the engine is started and independently of the other lights. Often they are incorporated within the same unit as the side lights or headlamps and care is needed not to confuse the different functions. When the side or headlamps are switched on DRLs will extinguish or dim to fulfil the side light role. Also where DRLs are in close proximity to indicator lamps, the appropriate DRL may extinguish or dip when the respective indicator is operated; this is by design and not a reason for rejection.

2. Supplementary Restraint Systems (SRS) lamps

When testing SRS MIL (Malfunction Indicator Light) lamps we are only looking to see if the lamp indicates if there is a fault with the system. If no lamp is present or it doesn’t illuminate then it can’t indicate a system fault, so it can’t be failed. Some vehicles may also incorporate warning messages on dash board displays; these are in addition to any MIL lamps and should not be used as a reason for rejection.

Where passenger air bags are present it is also often possible to disarm them, or they may automatically disarm where there is little or no weight on the passenger seat. This may be accompanied by a lamp permanently on to highlight the airbag has been disarmed, this is not considered a SRS MIL, and therefore isn’t a reason for rejection.

3. View to the rear

During the test we only need to examine the obligatory mirrors, or indirect vision devices, for presence and condition. Many vehicles have more than the mandatory number of mirrors or devices fitted and therefore a defect may not automatically be a fail. So before failing a vehicle for a missing or defective mirror, check to see if it’s classed as an obligatory fitment. If it’s not then it’ll only be an advisory item.


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  1. Comment by James posted on

    I've got my MOT coming up next month... it's a 2010 Audi A3 and I've half retro-fitted TPMS. The monitoring system has been activated in the car's module but I haven't installed the button on the dash yet to be able to reset the values on the TPMS system. As a result, I've got a TPMS warning light on the instrument cluster because I've since changed the pressure in my tyres and don't have a means to reset it until I install a button (unless I reset it via the diagnostics port).

    Is this a failure?

    I've read that TPMS errors are only a failure on cars registered after 01 January 2012 - is this correct?

    However, I was told by my garage that any light on the dash is a fail - is this correct?


  2. Comment by lisa posted on

    Hi my car has just failed its mot . The airbag warning light isn't on but in the dash it says airbag failure on the electric screen was they right to fail my car

  3. Comment by Steve posted on

    Hi there, I have a VW Polo GTI X reg which as an airbag built into the side of the car seat, that has gone off, and I also have the warning light on the dash.

    Cars of this model and age did not have seats with airbags built in as standard. If I replaced this seat with a standard seat (with no airbags built in), is that OK, or would I fail the MOT due to removing the seat with the airbag?



  4. Comment by wayne posted on

    My car failed on the airbag light being on this year it passed last year with it on :O(

  5. Comment by Matt posted on

    I carried out a repair on a vehicle due to an MOT failure, took the vehicle back to the testing station the next day, but the tester wouldn't issue a pass because the advisories has not been done. Surely the advisories are an advice and NOT a reason to refuse a pass?

  6. Comment by Jane Bryant posted on

    SRS Air bag light
    Please can you clarify this as the The M.O.T. Inspection Manual section 5.4 Supplementary Restraint Systems (SRS) States

    Method of Inspection
    Sub section 2: Turn on the ignition and check the presence and operation of any Supplementary Restraint System (SRS) malfunction indicator lamp(s) (MIL).

    Reason for Rejection:
    A Supplementary Restraint System (SRS) malfunction indicator lamp:
    • inoperative
    • ***indicating a system malfunction****.

    So surely your reply to Mike stating 'The SRS (airbag) warning lamp is not an MOT failure' is wrong.


    • Replies to Jane Bryant>

      Comment by Matters of Testing posted on

      Hi Jane,

      the section quoted is from an older version of the MOT inspection manual.

      In the current Manual, Section 5.4 Method of Inspection 2 states: "Check that the Supplementary Restraint System (SRS) malfunction indicator lamp (MIL) does not indicate a fault in the system". The corresponding Reason for Rejection states "A Supplementary Restraint System (SRS) malfunction indicator lamp indicating a system malfunction (page dated April 2013).

      You can find it here for more information

      Hope this helps. Kind regards.

  7. Comment by carl posted on

    So im still not clear on the Engine management light being lit during an MOT is it a fail no other lights on at all just this one

  8. Comment by Ben James posted on

    My car (a 2001 Renault Laguna) has the TPMS light lit up because the sensor is faulty. I read that the test is only applicable to vehicles from 2012 onward - does this mean that mine will pass the MOT next week?

  9. Comment by gurjit posted on

    I have an airbag light lit up all th etime on Audi A6 is this a MOT failure

  10. Comment by Mike posted on

    I failed a seatbelt on the passenger rear offside because it didn't lock when tugged, I enquired later and was told it didn't have to lock when tugged as long as it clipped into the catch o.k. The fact that the rear passenger could have head butted the driver in the event of a RTC seems to be a definite fail. Any reasons for this?

    • Replies to Mike>

      Comment by Matters of Testing posted on

      Hi Mike,

      An inertia reel seat belt not locking when tugged has never been a Reason for Rejection (RfR) for a good reason. This is because many seat belts use a pendulum type locking mechanism which only works when the vehicle is in motion. It is not possible to readily identify this type of belt, so if; 'a seat belt not locking when pulled' was an RfR, many perfectly good seat belts would fail and so would the brand new replacement.


  11. Comment by Richard posted on

    When are you going to sort out the RFR for TPMS light on . Its in the RFR column but the box isn't there to click on !!!!

    • Replies to Richard>

      Comment by Matters of Testing posted on

      Hi Richard,

      The reason the TPMS RfR isn't available is likely to be because the vehicle is outside of the scope of TPMS inspection, in which case MOT Comp prevents its (incorrect) use.

      The Inspection Manual states that "The inspection of the tyre pressure monitoring system (TPMS) only applies to passenger vehicles with:

      · four or more wheels, and
      · not more than 8 passenger seats excluding the driver’s seat, and
      · first used on or after 1 January 2012

      The check does not apply to quadricycles."

      Therefore, if the vehicle is older than 2012 or not a Class 4 the RfR will not be available. In the event that the vehicle does meet the Manual criteria, then a fault should be logged with the help desk.

      Hope this helps. Kind regards.

  12. Comment by Shad posted on

    Bmw 520 failed mot srs warning lamp indicates a fault (5.4.2). Is this correct?

  13. Comment by Laura posted on

    My left indicator light doesn't work on my dash but works on the outside of the car. Will this be an mot failure? Thanks

  14. Comment by hellen posted on

    I have a cittoen c2 been in for its mot today and its been failed on SRS warning lamp indicates a fault (5.4.2) is this correct or should it have been an advisory??

    • Replies to hellen>

      Comment by Matters of Testing posted on

      Hi Helen. Thank you for your question. They were correct to fail the vehicle in this case.

      Kind Regards.

  15. Comment by mike posted on

    i have an american car with abs and air bags made in 1993 but does not have these warning lights on dash so for a british mot how do i stand ??

    • Replies to mike>

      Comment by Matters of Testing posted on

      Hi Mike

      The SRS (airbag) warning lamp is not an MOT failure. However, if a vehicle is fitted with ABS it must have an ABS warning lamp regardless of whether one was fitted as original equipment.

      Kind regards.

      • Replies to Matters of Testing>

        Comment by Saidy posted on

        I accept that malfunction of an Air bag is a EU directive and has to be implemented. However,common sense has to prevail and argued against if and when a vehicle presented with an Air bag light on is a failure, following which the bulb removed becomes a pass, a loop hole, makes no sense and a mockery of the safety feature. Is the EU aware of the implication.?

  16. Comment by Adam Mark posted on

    Hi, Thanks for the update… really informative article...

  17. Comment by Pat Durham posted on

    Hi my daytime running lights (factory fitted)on my alfa Romeo giuiletta (Nov 2010) have stopped working.
    Will this be an MOT failure ?
    Thanks Pat .

    • Replies to Pat Durham>

      Comment by Matters of Testing posted on

      Hi Pat. Daytime running lamps are not part of the test, unless they adversely affect any other lamp. Hope this helps. Kind regards.

  18. Comment by Ian Doherty posted on

    Is the engine management light illuminated a fail...thanks ian.

    • Replies to Ian Doherty>

      Comment by Matters of Testing posted on

      Hi Ian, no this isn't a fail. Many thanks.

      • Replies to Matters of Testing>

        Comment by Gordon posted on

        If engine management light is on and message on dash States pollution fault is that a fail

  19. Comment by Syed posted on

  20. Comment by sara posted on

    Hi just wondering if a car fails an mot if the mileage can not be seen clearly?

  21. Comment by Jamie posted on

    I come across this kind of problem on a regular basis light stays on at time of test then comes back with light not working at all, pass and advise ok but shouldn't this be like the abs light if it does not come on if fitted should fail too.
    So many people out there trying to just get there car to pass regardless of the actual fault and cost. In the event of a motor accident the first thing that gets questioned is the MOT testing stationand the Nominated tester.

  22. Comment by Nitros44 posted on

    With regards to the DRL lamps the inspection manual states in the info column that DRL are testable if they replace the front postion lamps ( section 1.1)

  23. Comment by steven humphreys posted on

    srs mil not illuminating .........PASS with advisory........cant be right surely, just encourages people to remove bulb, and the poor sole who's the next owner of the car may not realize there's a fault on the srs system while he's driving his wife and kids around, that's the reason for visual warning on the dash in clear view.

    • Replies to steven humphreys>

      Comment by Matters of Testing posted on

      Hi Steven,

      The test of the SRS warning lamp, along with a host of other items, was only introduced into the MOT test as a result of Directive 2010/48/EU. These new items were going to increase the complexity to the test at a time when the political ideal was to reduce the regulatory burden. For this reason, our remit was to include nothing additional in the test that was not required by the Directive.

      As a result, an SRS MIL indicating a system malfunction was included, but as the Directive does not specify a failure for an SRS MIL being inoperative this could not be added. For the same reason, SRS checks (and other 'new' checks) do not apply to Class 3 vehicles.

      However, to keep things in perspective, it must be remembered that 'SRS', as is in the name, is a supplementary rather than a primary safety system. Also we are now checking a host of items that were not previously included, so it is a step in the right direction.

      Kind regards.