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What is the definition of insecure and how should it be applied during an MOT test?

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Insecure brake part

We‘ve had many questions on this subject, particularly in relation to batteries. A previous article gave guidance that a battery would not be deemed insecure unless it is likely to fall from vehicle under normal use. So how do we arrive at this conclusion?

The term ‘insecure’ is used when a component or item is defective due to movement between it and its mounting or attachment to the vehicle.

There is criteria set out in the manuals for assessing wear, but NTs are also expected to use their experience and judgement while considering a component’s function when assessing security.

The criteria to be used when assessing security is:

  • whether the movement has reached the stage where it is obviously likely to affect the roadworthiness of the vehicle
  • whether the component is not safely attached and has clearly reached the stage when replacement or repair is necessary

For example, when inspecting a steering box, any movement between it and its fixings would be enough for it to be considered insecure. A motorcycle brake lever would be considered insecure if it could readily be moved on the handlebar.

Also a headlamp would be deemed insecure if it was free to move and so alter the aim position, while a rear position lamp would need to be in such a condition it is likely to fall from vehicle or not face the rear.

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  1. Comment by Faisal posted on

    My car failed an MOT yesterday due to battery being insecure. The battery is clamped down and hard to move with a single hand so I asked the tester to explain what needed to be fixed. He held the battery with both hands, shook it really hard and it moved a couple of inches on each side. Is that really how it is supposed to be tested? I haven't seen a vehicle which has the battery drilled into the body (maybe that's the case with newer cars) but in case of older cars, how many cars will pass the test if you test it like that? Why is it left to the tester's interpretation of how tightened they want the battery to be to be considered secure?

  2. Comment by keith posted on

    Hi im Keith and have just finished a refresher course at Lincoln 12/01/ 2015 I to asked the question about battery security after a long discussion the outcome was if not defiantly fastened down then pass and advise as it cannot fall over in its own space, the question isn't can it fall over, its weather it is secure and the definition in the dictionary, and I quote, is something that is fastened securely unquote.Basically something that has its own fastening.

  3. Comment by Matters of Testing posted on

    Hi everyone

    Thanks for your comments. We understand why some of you have concerns about assessing the security of batteries.

    It’s important to remember that the MOT test is only to check that the testable items meet the minimum standards of roadworthiness required by law.

    Some of you suggested that a battery that’s not clamped down could bounce up, such as when going over a speed bump, and cause a short circuit. This would be extremely unlikely, given that:
    • many vehicles have sound deadening material fixed to the bonnet
    • many batteries have a rigid plastic cover
    • many positive battery terminals have a rubber cover
    • many battery leads are too short to allow the battery much movement

    In this article we point out that part of the assessment is: "whether the movement has reached the stage where it is obviously likely to affect the roadworthiness of the vehicle". Therefore, if a tester thinks that an insecure battery is obviously likely to fall or cause a short-circuit then a fail would be justified.

    We hope this information helps.

    Kind regards

  4. Comment by Chris Ives posted on

    Surly if a battery is insecure enough to fall off in normal use, it would have done on the way to the VTS?

  5. Comment by MR S A MARWARI(ali) posted on

    Dear Sir
    every new car has BATTERY clamp or braket WHY to keep the battery insecure,other wise why would they do that,many cars have room for battery to move,roads of nowday have humps or bumps holes on the road,keep a water bottle of in the car and see what happens.

  6. Comment by Eric u posted on

    I thought if it was so loose to ark the positive terminal it would fail not fall off the car

  7. Comment by Ben posted on

    There are a number of battery's that if insecure would in the event of an RTC short both terminals against the Bonnet or other metal work. Clamping the battery tight may not stop the problem in a major RTC but will help in the case of minor incidents. They could fall out if the car is on its roof or side if insecure.

  8. Comment by Geo Berry posted on

    I find it strange that for years testers have been incorrectly failing insecure batteries.
    Now that it is a fail Item, it seems we cant work out what to do!

    I do wonder why it was made a fail item when all definitions of insecure will in all probability never be applied to a battery in a modern vehicle, as quite simply there isn't room for it to fall anywhere!!

    • Replies to Geo Berry>

      Comment by william foreman posted on

      i consider whether a battery can move UPWARDS if going over a bumpas insecure, as the terminals could arc out on the bonnet and either cause the battery to spark and cause a fire, in some cases a battery could expload if it is faulty (mercedes had a recall for batteries that were liable to explode on their C class)
      also if there is a bolt or stud that could pierce the side of the battery and cause acid to leak out. each vehicle produces its own risks for assessment

    • Replies to Geo Berry>

      Comment by Daniel Booth posted on

      I was in a VTS the other day to pick up a vehicle my garage had passed on for them to test. I overheard a customer picking their car up and receiving the refusal certificate stating battery insecure. The MOT Tester then went on to explain that he had failed her Vauxhall Astra for an insecure battery as the clamp was loose and it was causing the battery to rattle around the battery tray. The customer agreed and arranged to get a new battery clamp fitted, yet surely the MOT Tester should have just manually advised and informed the presenter on the battery being loose and not failed as it certainly wasn't likely to fall from the vehicle.