So many systems failing - any ideas as to why?

[ThomasG]

I recently posted about the ACC issue - no answers here, but Audi Glasgow are trying to sort it. In the meantime, I've had the car back over the xmas hols, all great...until this morning when I started it up and I got stop start unavailable, then tyre pressure warning, then stabilisation warning, then abs, then air suspension failure...then parking brake!

Only ABS in orange - so I drove slowly to the local garage where I bought it from, and all the lights went off, but the parking assist light on the button was flashing, I switched it off manually...then they came on again as I pulled in. We are all at a loss - but it does go back to Audi Glasgow for ten days while I am out of the country, and these errors will no doubt show in the history.

Has anyone experienced this, or can point me to anything? The car is under warranty from the garage I bought it at, so it's not costing me anything. But if it's not fixed, it goes back...

Probably the nicest car to drive I've had - beats my TVR Tuscan as it's quiet!! But I am now despondent ...

Thanks in advance.

[Magnet]

Hello Thomas, 

I’m hoping there’s no need to be despondent! 

Really sticking my neck out here, but sounds like classic, barn door battery failure/inefficiency. 

All the systems you mention depend on battery efficiency within fine limits. Gone are the days when a battery’s serviceability was simply judged on its ability to start a vehicle! 

Notice the car is now approaching 7 years old, which for a stop/start facility vehicle is pretty good to very good - assuming the original battery hasn’t already been renewed, which would not surprise. 

Where from here? If the battery is found to be the culprit, in my mind the quality of the replacement is of paramount importance, and if the supplying  sales garage is fitting the bill under warranty, then you are likely to end up with the cheapest make their local motor factors can supply! 

If it were mine, I would be insisting on replacing it with say a Varta (original equipment) one even if you have to pay the difference.

Perhaps you can let us know how you get on.

Kind regards,

Gareth. 

 

[ThomasG]

Gareth, that makes sense. I had a stop start error a week ago, then it went. 

I'll take it to them tomorrow. 

I wonder if this may be affecting the ACC too?!

£400 for a battery!! Ouch. 

Thanks

T

[Magnet]

Hello Thomas, 

Where on earth does the £400 come from?

Tongue in cheek - come on, I thought you Scots were a close second to the Welsh in the wallet preservation society! 

We bought a Varta for a 3 1/2 year old Evoque ( yes confirmed three and a half years old) from Tayna Battery for about £135 (even the JLR dealer retail price was ‘only’ £275). These batteries don’t come much bigger/costlier than that one! 

I would advise taking the dimensions of yours, taking all the information off the label inc. Ah. CCA current rating etc. and spending half an hour on the good old eBay searching under Varta or Bosch battery for your particular model. You will probably come up with suppliers such as Tayna, Battery Megastore, Plymouth Batteries etc. 

Alternative way of doing it:- look up their direct websites and input your registration number. They will list the correct one. Or better still ring and have a chat with them. Beware, you are likely to find they charge you carriage if ordered direct, but you get it delivered free if ordered through eBay! Why?? 

Happy hunting and money saving. 

Let us know how you get on Thomas. 

Kind regards,

Gareth. 

 

[ThomasG]

It was on Europarts!! But I see the ones on eBay now. Don't recommend a Halfords one then? 

How would one check the battery? If I take it to the garage tomorrow, they can check it - what are we looking for? Or shall I see if they have one to put on and if it all works then your theory is proven!

T

[Magnet]

Hello Thomas,

A strictly personal opinion, but Euro Car Parts can appear to be an attractive seller to those who follow discount codes - which they frequently list. As with all % discounts, the all important figure is the actual stated retail/starting price to which the % discount is applied, and it’s not uncommon to find their final discounted price is higher than its competitor’s ‘normal’ price, and indeed it’s own sub companies such as Car Parts 4 Less. 

Halfords?? Simply compare their prices with those listed for quality makes with some of the online suppliers already mentioned. The answer is there, and is generally not even worthy of second thought.

Checking batteries? Indeed Halfords can usually check the efficiency of batteries ( recommended to be checked after at least a 10 mile run). If found to be substandard, do you buy a new one from Halfords? Depends whether the above is of any concern. How comprehensive are Halford’s test?? 

Having researched best price for on line purchase of a quality battery and found it to be £x (I would anticipate far less than £200), do you gamble spending this money as a possible (in caps) cure, or just spend more money on trying to diagnose the issues.  This has to be a personal choice Thomas, and will depend on how low £x is after you have done your best-price homework and the hassle factor in presenting the car for further investigation and dealing with the seller. 

Of course, it has to be appreciated that advice given on here is free, and although based on personal experiences and logic, may not be accurate, but I would like to think folks who contribute on here do so as if they were in the situation of those asking for advice, 

Perhaps you could let us know how you get on.

Kind regards,

Gareth, 

 

[ThomasG]

Ok - car back to vendor garage - battery is just holding a charge, it's below 12volts and the engineer there agrees it's the battery. Well done.

They are going to replace it with like for like, and take it to Audi themselves next week. I am going to get the VAGCOM output from Audi and post it here, the hivemind of the forums may see something that can expedite the matter.

I am away until the 21st, so I expect a lovely new car when I get back!!

Thanks again.

[Magnet]

Well done Thomas. That saves the worry of why you have been moving towards a full set of Christmas tree warning lights. Audi dealers eh!? Good isn’t it?

Sometimes the forum gets it right, sometimes wrong, but we have to try to fathom these things out without the offending vehicle. 

Remember, if we are wrong at least we are cheap! 

Good luck with it.

Kind regards,

Gareth. 

[ThomasG]

I shall let you know if it all comes good when they out the battery in! 

Thanks again. 

[ThomasG]

Well, bad news. New battery was needed, but the faults are all still there.

They ran a check with their scanner and the ABS module got an implausible response.

We have requested the full vagcom output so I can post it here.

I wonder if a failing ABS module could trigger all the rest of the warnings, or even the ACC Brake assist fault?

It's in Audi today, and I return from my travels on the 21st. That should surely be enough time to fix it - as it's under warranty, I would expect it to be fixed in 12 days!!

Will advise

Thanks again for input. I don't want to hand the car back, but I will if it's not fixed...or ask for like for like replacement - one that works!! But there aren't many biTDi' for sale. With low mileage...

 

[ThomasG]

Here was the scan at the garage - not vagcom obviously

[Magnet]

Hello Thomas,

Part way there then! 

ABS system? In my experience, the (earlier only?)  ABS units themselves were not without problems, and at one time you could buy part-units where the valve block section could be replaced as part of the original unit. Things have moved on and these units are now generally trouble free?? Don’t know.

ABS and individual wheel sensors? ‘Wheel speed signal...........’.     Sounds a bit vague as a diagnosis to me. Which wheel?? 

Wheel sensor issue? Or weak built- in magnetism (on rear hubs?) which signals the sensors. 

Watch this space then. 

Thanks for keeping the forum informed Thomas.

’..don’t want to hand the car back..’ For what it means, I would be of the same mind - it’s sortable without cost you. Inconvenience of course, but.....

Kind regards,

Gareth. 

[ThomasG]

Update from Audi. 

I am assuming this is just the dash lights, though it seems to infer it's the cause of the ACC issue too. 

"Our technician has Identified the bearing as defective and has damaged the pick up sensor. As the systems are all linked, this is the source of all your warning lights showing on dashboard."

[Magnet]

Hello Thomas,

Thanks for coming back on this. 

The ABS is signalled (certainly on the rear wheels) by a very weak magnet set into the rear hubs - too weak to be detected by attracting a piece of steel in my experience, but there anyway. This ‘magnetic signal’ is picked up by the attached ABS sensor. 

If this magnetic signal becomes too weak, then it obviously affects the whole ABS system, and technicians will tell you it’s a ‘bearing (failure) issue’, although the bearing itself is likely to be serviceable - but the bearing hub’s inbuilt magnetic field is the problem - and results in the need to renew the whole hub.

If the bearing ‘has damaged the pick up sensor’ (as you have been told) then the bearing will have been completely shot and you would most certainly have noticed it’s protesting noises. Personally, I would go with my above explanation, but.... ‘Damaged pick up sensor’’ will mean they will replace that sensor although it could be serviceable. Cost of new hub and sensor and fitting?? Not cheap, but as I recall, this will be warranty work, and if carried out at main dealer then no need to worry about whether aftermarket parts might be used. 

5 year old car suffering from weak ABS hub signal? Bit unusual? 

Good luck with getting it sorted.

Kind regards,

Gareth.

[ThomasG]

It's not cheap fix, but it's under warranty. 

Will hopefully hear tomorrow. But it's the ACC thing I really need addressing. 

T

[Magnet]

It would surprise me if the adaptive cruise control isn’t influenced by the efficiency of the ABS system, so any fault n the car’s braking system might (will?) render the ACC inoperative. It would be taking chances if it wasn’t . 

Kind regards,

Gareth. 

[ThomasG]

All lights off!! Got a long drive tomorrow so I'll see if the ACC thing is fixed. 

On another note, how can I get a full VAGCOM output to post here fur the hive mind, should something happen again? Are the eBay non-branded things any good, or should I look for someone local with the RossTech kit?

[Magnet]

So did they just change the hub (bearing) and the ABS sensor, and didn’t replace anything else associated with the now fault free ACC?

Kind regards,

Gareth.  

[ThomasG]

That's what the work sheet states. But I have yet to drive it. 

[ThomasG]

Drives brilliantly, as it always has - no dash lights -  but the ACC/Brake assistant thing came on after 25 miles or so. 

I may start a new thread for this one. But it did clear after 5 secs - the warning triangle came on, then went off. But it occurred again and again on the way to Glasgow - but the triangle didn't stay on as it used to...

I have no idea how to get the VAGCOM readout that I see posted in other posts about this fault - but I'll see if anyone has one.