MOT - am I being taken for a ride?

Wife took our car in for an MOT last Thursday and also asked them to fix failed heater blower motor. They called back to say the car needed two new tyres, but they wanted to keep it in overnight awaiting parts. They also said that the ABS warning light was coming on intermittently.

Picked it up on the Friday, two new tyres, MOT pass with advisory 'Intermittent ABS fault'.

Problem is that when I took it out on Saturday the speedometer and the computer screen were dead. And the ABS warning light was on constantly.

Went back on Monday, lass on reception 'had a word' with the chap who had done the MOT and he said that the speedo/computer failure was because of the ABS fault. I scratched my head and went away. But surely:

• If ABS was faulty when the car was taken in, why were the speedo and computer still working - which they certainly were- if the explanation is correct?
• If the explanation is correct the ABS fault must have developed while they had the car.

Well, we've got the car back with a valid MOT despite it having two major fails - non-functioning speedo and malfunctioning ABS which weren't there when wife took it in.

I don't know anything about car mechanics - does this make sense to anyone who understands these things?

Robin.

You're better off taking your motor to a competent auto electrician, they really are good at these things when the weirdness starts

Our Citroen HDI totally conked out after an intermittent service fault bleep for about 2 weeks each time the car was started

in temper, the Mrs opened the bonnet and battered the plastic casing top covering the battery

...and the car worked perfectly after that

Now we whack it with a garden hand tool if it plays up

All the connections seem to be fine but something obviously isn't, large temperature changes seem to set it off and battering it sorts it out

With the Merc van the abs fault was actually crap software and a dealer upgrade sorted it out

There's a reasonable chance that a good auto electrical guy has already seen your fault before now

Edited By Ady1 on 14/09/2022 00:20:58

I believe your car would/should not have passed the MOT without a working speedo. Sounds like they had a fiddle about and never even realised they had made things worse after doing the MOT. Check fuses.

I wouldn't let a spanner monkey dig about with your electrics, even if he was the cause

My wife has always insisted on me taking her car for repairs - she knows, from the past, that some try to ‘pull the wool’ and invent faults.

Tyres? Get them checked at a reputable tyre company.

Electronics - checked by someone who is properly capable. The fault (if there was one) was likely at one of the wheels where a sensor picks up the wheel rotational speed from a reluctor ring on the drive shaft or whatever.

I was once quoted £450 just for a complete new drive shaft, when a £3 reluctor ring was all that was needed. The dealership were simply contracted to only supply new parts from that manufacturer, so could not fit a new reluctor ring. When I supplied the part, they were quite happy to fit it.

The same happened for a failed electric window winder. £170 (plus VAT/) from the manufacturer but £19 from a parts supplier. The garage was quite happy to fit the one I supplied, but they could not order on in from anyone but Peugeot.

Somehow I doubt the abs fault was there prior to them getting the car - unless they checked any fault codes recorded. It should have been fixed, IMO, but may not actually fall within the MoT rules. The test certificate is only valid at the time of the test, so if the braking balance and efficiency were OK at the time of the test…

My understanding of this affair is that you were short-changed with some sub-standard work and possibly fraudulently over-charged. Find yourself a good, honest repairer. Let them arrange the test after them checking the vehicle first.

One proper mechanic I used, until he died, always gave the vehicle a cursory glance, then took it for test and then rectified any faults found before re-testing later that same day. It’s one reason why they report so many fails, these days. 🙂

Modern car electronics are a riddle wrapped in a mystery inside an enigma to me. I had, apparently, one LED fail in a rear light cluster on a Volvo V90 which brought up all sorts of intermittent and contradictory fault indications on the dashboard. The local Volvo specialist (after many years no longer an authorised Volvo dealer) had it in the workshop for a week before they found the fault and charged me £675. Obviously, I had no choice other than to smile through gritted teeth and cough up.

Are you in the aa or something similar. If so they will come and tell you what the abs fault is. It could be just one of the wheel sensors that are generally very easy to replace as long as you don't snap it off in the hub. I had a 4 wheel drive gearbox overheat and that was down to a wheel sensor. They are definitely not used just for abs.

I believe any warning light on the dash is an mot fail now since about 2 years ago. I would presume it wasn't on when they trested as they sound like they would have liked to charge you for a fix.

When my wifes car broke down the AA came out and towed it to a garage as the fitter said he could not look for electronic faults on the roadside. A full AA check on a car costs £128 for AA members (£142 for non-members),

regards

This may be of interest, Robin : **LINK**

https://www.gov.uk/getting-an-mot/problems-with-your-test-result

MichaelG.

Very Much agree

Very much agree.

That's interesting, maybe as I had a gearbox overheat and not an electrical problem he went ahead and plugged it in. Either way he told me it was my back left wheel sensor and I got it fixed myself.

It is probably impossible to be sure one way or another.

Intermittent ABS light could be indication of some loose connection or other failure which just happens to get worse after MoT.

OR maybe they had a look, didn't find anything, but failed to connect the speedo wires back up solidly.

OR, in fixing the blower, they had to disconnect the speedo (not uncommon), and didn't plug it back in correctly.

I'd be slightly dissapointed with this : "'had a word' with the chap who had done the MOT and he said that the speedo/computer failure was because of the ABS fault".

Was MoT guy the same who originally noticed the fault (and implied it needed looking into)? If not, did they look into the fault? Check your bill... does it include any fee for investigation? Did they fiddle with speedo during the blower fix?

Ideally I'd want a garage that showed a little more concern.

It seems that often the indicated fault is triggered by a fault elsewhere. Have seen a YouTube video with an indicated right wheel abs fault which was a broken wire on the left. Take it to a competent electrical vehicle engineer but expect a hefty time cost. A friend had a Volvo, drove it home from a holiday, emptied the luggage then later noticed the side lights on and the car wouldn’t start, four months later and numerous part replacements before he could use it again.

The ABS system is also used by the speedo, Odo and the traction control if you have it.

Intermittent faults sooner or later become permanent. Reluctor rings break for no apparent reason, but these either fail or work OK there is no maybe.

It might the worth (after checking the fuse for the dead screen) checking the cables going to both front hubs for signs of scuffs in the dirt coating which may indicate interfering fingers or someone dropping the wheel on a cable when the tyre was changed.

BTW Don't go back there next year

Edited By Dave Halford on 14/09/2022 09:54:34

Here in Rugby we have an MOT test station that does MOTs, and nothing else! I've been using them for 40 years. There is no pressure on the chaps there to invent faults or even cause them and if they say something is wrong, it is.

I'm afraid i don't trust any garage that tells me the car's got a fault that wasn't there when I took the car to them.

I had an intermittent ABS fault, eventually fixed by expensively renewing the relevant hub with rotor and sensor.

I think that the fault should result in an MOT failure.

An MOT inspector I used for many years told me that, if he felt a car was borderline, he'd consider if he'd be happy to drive it to London (140 miles) in that condition. If he would he'd find a reason to pass it, if not he'd find a reason to fail it.

That's probably a pretty fair application of vehicle inspection and repair experience.

Plus sometimes it's not just the nature of the fault itself but what it exposes of the skills and understanding of previous workers on the vehicle, and what other matters might have been affected.

I'd rather trust a vehicle to somebody who works like that than one working solely from a ticksheet.

Find your local council-run MOT centre. They have NO financial interest in finding faults.

Neil

Sounds to me like they "broke" the instrument cluster when changing the blower. You are correct a faulty speedo is an MOT failure.
Did they tell you about these faults when you picked it up?
The problem is proving it was them, however the speedo must have been working at the date and time recorded for the MOT. The probability of it failing overnight at worst is tiny. Any reasonable person would agree. If it did just happen to fail while the car was in their care that's just a cost of doing business. I would suggest you talk to them nicely and say that it most have been something they did and ask them to commit to fixing it, either themselves or by a specialist at their cost. If they don't agree to this tell them that you will get it fixed elswere and recover the costs from them by means of the small claims court. If they still refuse go ahead and get it repaired and open a claim. It's easy to do on line and low cost. Even if the garage does not pay up right away and it goes to a judgement if ther is any doubt in cliam aginst a business the judgement goes in favour of the consumer.

You don't say the make model or age of the car but this sort of fault can literally write off a modern car. It could need a whole new instrument cluster costing thousands. Some models of car you can't even fit a used one because they are "coded" to the car. With a used cluster you may end up with incorrect mileage which reduces the value of the car.
Technically you should get the speedo fixed ASAP as it's a safety issue. At least put a GPS with speed readout in the car so you can avoid a speeding ticket.

I had a similar issue with a trusted local garage. They changed the front spring on SWMBOs Focus and next day I noticed the headlamp levelling wasn't working. They had broken the link between the lower arm and leveling sensor. They tried to deny it initally but finally agreed to the logic. They had to replace the whole sensor. He showed me the bill for the part from Ford, it was more than we paid for the service, spring and MOT. 90% of Focus models don't have this sensory and the just let the arm and hub drop down like normal.

Robert G8RPI

Edited By Robert Atkinson 2 on 14/09/2022 17:44:50