Car not repaired, now requesting more money.

breezerboy

Hello all, long time reader, but only just joined.

I'm after your opinions on a repair we're in the process of, hopefully, getting sorted.

We have a 2004 Mercedes Viano Ambiente and mostly love it. About 8 months ago it developed an intermittent fault. Occasionally, upon trying to start the car it would come up on the dash - "coolant visit workshop, display faulty visit workshop" and no P symbol in the display for the gearbox. When this happened the engine wouldn't turn, nothing at all. Turn off, remove key, try again - sometimes it would start straight away (with no faults showing), other times it would take a few attempts. This could be twice a day or once a fortnight at random. If the P symbol came up, regardless of other fault warnings the car would start.

In May, Mercedes had the car for 2 days and reported back suspecting an ECU fault but not 100%. sure, so nothing changed at this point.

Pretty much no issue (seemed improved if anything) until October when the engine turned itself off (thankfully at 10mph) leaving us to coast to a stop. Same symptoms as above, but after 1/2 hour of trying got recovered by AA. OBD2 port wouldn't connect to scanner/laptop. Nothing touched for 2 days then it started and no issue.

Mercedes had the car again with the request to "trace and fix the starting issue".

After 2 weeks and us £900 poorer we had a new Electronic Ignition Switch fitted and were told all was now good.



2 weeks later, we had the exact same issues again.
We informed Mercedes and they had it back to rectify.
Another 2 weeks without the car and a new steering lock fitted (no extra charge) - again told all was now good.



10 days later, guess what. Exact same issue.
They have now had the car for another 2 weeks and today they told me it they had found the problem. It would be an additional £1400 for a new gearbox loom, gearbox processor and fix the gearbox leak that had put oil in the electrics. Apparently they have traced this to be the original problem (sounds likely considering the original symptoms) as the gearbox processor isn't telling the main computer it's in park, but does send a few other random signals causing display/coolant warnings.

Question is, should they have spotted the gearbox issue earlier/originally, especially considering the slight gearbox oil leak and lack of P symbol on the non starts.?

I don't want to name and shame (yet, if at all), but I am left wondering if the EIS needed to be changed or was just a guess and/or this could have all been sorted a lot sooner.



Another problem is they told us today that the car was currently unusable until the repair was carried out, but we need it for Christmas family holiday (400 miles and 10 days so hiring a large enough car - 7 seat - is an unnecessary expense).


I assume the Supply of Goods & Services Act 1982 applies to some degree if it can be shown that they could/should have spotted this earlier - didn't take due care?

Our current intention is to make payment under protest and try to claim back later as we need the car. If so, do we claim back for the additional cost - we contracted them to fix the starting issue which we were told would be £900, not £2300, or do we claim for the original £900 - they were in breach of contract as they didn't fix the car? We paid via credit card if that helps.


I look forward to your opinions.

Many thanks

Nigel

forgotmyname

Some issues can be hard to diagnose.

Its like me saying find the needle i put in that haystack. How long should it take you to find it? Minutes, Hours, Years?

I would be asking for a refund of the £900 of parts that did not fix the issue and come to some compromise on the bill.

And ask them will this cure the issue finally?

philatio

Get rid.

My parents had very similar issue.. but with a Toyota Yaris. Pretty much the same faults and after a few different fixes they came up with it 'definately' being the gearbox loom.

£1000 paid

6 months later.. problems start again.

They just got rid.

CrazyRed

Your vehicle will have the Mercedes 722.6 gearbox, as it's an Auto.

There is a known issue with this gearbox where the 'pilot bushing' (as it is called - £21 from Mercedes) has an O-ring fail and the oil 'wicks' up the loom to the transmission ECU. The revised pilot bushing, apparently, doesn't suffer with the issue - it's only the original ones!

The cure is a new pilot bushing and (ideally) new fluid and filter in the gearbox (approximate cost £180 at a decent Mercedes Independent - don't let it anywhere near the dealer for this work unless you like wasting money).

The loom and ECU can be cleaned out and full operation will then be restored.

Suggest you have a look at the Mercedes Owners Forum (http://forums.mercedesclub.org.uk/index.php), search on there for the 722.6 pilot bushing issue and understand what is required to resolve the issue, then book it in with an independent in your area and get the work carried out.

You might get a partial refund on the EIS (Electronic Ignition Switch) but don't hold out too many hopes - the part is uniquely coded to your vehicle and, once removed, is no use whatsoever to another customer/car - I understand that the EIS cannot be reprogrammed (apart from one particular person in the UK who MAY be able to carry out this work).

How do I know this? I own a Merc, with the 722.6 gearbox and I had the work I mentioned above carried out as a preventative measure!

HTH

breezerboy

forgotmyname wrote: »

Some issues can be hard to diagnose.

Its like me saying find the needle i put in that haystack. How long should it take you to find it? Minutes, Hours, Years?

With the right equipment, a few hours, but I do get your point. They supposedly have a few thousand pounds of diagnostic equipment and knowledge about known problems. I posted the symptoms (just the 3rd paragraph from original post) on another Mercedes site and had the same diagnosis within hours as Mercedes have taken 6 weeks.

I would be asking for a refund of the £900 of parts that did not fix the issue and come to some compromise on the bill.

And ask them will this cure the issue finally?

That's the plan.


Many thanks for the info CRAZYRED. Do you know of anyone who can test the removed loom and ECU or would they have to be re-fitted to test after being cleaned? I only ask because they told me the parts MUST be replaced and the vehicle is totally unusable until this is done. This annoyed me a bit as the car was driven to them with an intermittent fault, not towed due to being immobile.

CrazyRed

They're talking out of their bums, Breezerboy. The ECU won't need testing, it'll only need some electrical contact cleaner to clean up the pins, then it can be temporarily reinstalled and the vehicle driven. Have a hunt around on the site I gave you earlier (or, if you're on there, mbclub.co.uk - both are damned good resources and full of information) for details of what needs doing when the loom's been contaminated - from what I remember, neither the loom, nor the ECU need replacement.

Don't let them talk you into replacing the gearbox ECU - the ECU's are specifically coded and 'tuned' to YOUR gearbox. Changing the ECU is far, far more than a simple plug-and-play operation. Before the vehicle can be started, the "new" ECU will have to be coded and programmed via STAR, which adds yet another layer of expense for you.

Just get them to refit the loom and ECU - as long as they haven't tried to open the ECU then it'll be fine once cleaned - transmission oil is non-conductive, so won't have damaged or shorted anything inside.

You might need to get the ECU and loom cleaned again once the independent has changed the pilot bushing, but a half-decent indi will advise you of that at the time. Which area of the country are you? The MB Owner's forums have a "specialist finder" that you can use to find a recommended indi.

(Incidentally, the reason for the spurious messages and the cutting out is because the transmission ECU is on the CANBUS and if the CANBUS signal fails (through the transmission oil insulating the ECU pins utilising very low voltages that the CANBUS uses), then ALL ECU's linked to that particular 'bus are shut down as a damage limitation exercise - the engine and transmission are on a different CANBUS to the other ECUs within the vehicle).

For proof that "only" cleaning will resolve the issues, please see post 10 in this thread:

http://forums.mercedesclub.org.uk/showthread.php?t=123229&highlight=pilot+bush

DIY repair/procedure : http://forums.mercedesclub.org.uk/showthread.php?t=98274&highlight=pilot+bush