Fault Code 3490 - Help (Newbie)

[ZenaBN]

Hello, I recently purchased my first Z4 and am loving it, however, I have experienced a few issues. I'm hoping I can get some advice on here for one of them please!

So I noticed that my fan comes on within 10 minutes of driving the car from cold and it's incredibly loud. Doesn't seem right so I had it scanned and the following came up:

BimmerGeeks ProTool
Model: Z4 sDrive20i
Engine: N20

Code: DME/DDE [MEVD174K] | 3490: Characteristic map thermostat, activation: Line disconnection

EDIT:
I have taken readings of the temperature and water pump which seem to be running normally so there's no reason for the fan to think it needs to be on full. It sounds like a jet!

I have tried Googling the code but I cannot seem to get anywhere and although I know there's a problem with the fan and I have the code I'm not sure exactly what the problem is or how to fix it!

I'd be very grateful for your advice

Many thanks in advance.

Sarah

 

[B21]

Its most likely an internal failure of the thermostat sensor..calls for a new thermostat..

Its in that class of faults that a substitue is often the only way to prove it..

 

[ZenaBN]

Thanks for your advice. The car is under warranty so I will contact the dealership and get it looked into further!

 

[B21]

Thanks for your advice. The car is under warranty so I will contact the dealership and get it looked into further!

For sure..I assume it’s not a bmw dealer?

Usually they (non bmw non Indy) struggle with these things….

 

[ZenaBN]

No it's a second hand car dealership called Williams Motor Company in Crewe. They sold the car to me knowing the NSR alloy had been welded 3 times and had a further 2 fractures. The car was advertised with silver wheels which they sprayed black to cover up curb marks but they did a very poor job. The low tyre pressure warning light came on a couple days after I bought it due to one of the fractures and when I looked back at a video taken of the interior from the viewing I noticed the low tyre pressure warning light was on then too. Oh and they own the MOT station which is where it passed it's MOT with no advisories and had a 'service' the day before I collected it.

Also the low coolant light came on the day after I bought it, turns out it was almost out of coolant, so much for the service! I did a hpi check before I bought it so just hoped it was a genuine car that'd ended up with a rubbish dealership! Now there's this problem with the fan plus there's an occasional grinding metal noise coming from the OSR wheel and although it's had new discs and pads one of the pads is really worn already. I don't want to give the car up, I just want it sorted.

 

[Scubaregs]

I'd be reporting those concerns to VOSA, if you think they have put an MOT on the car when it should not have passed.

 

[ZenaBN]

Yeah good point. The trouble is proving that they knew...

 

[Scubaregs]

Yeah good point. The trouble is proving that they knew...

If you think there were faults on the car that meant it should not have passed the MOT, you should be questioning it.

 

[B21]

Well don’t drive the car any distance (more than 4 miles) with that fault…

Sounds like it needs some real love…

That class of dealer are completely useless when it comes to these faults…

If it’s not too late you need somebody like the AA / RAC SME to look at the car and help you negotiate your issues …

Fundamental issue is that the dealer probably hasn’t got the margin to sort it..let alone the competence… :tumbleweed:

 

[ZenaBN]

As long as the low tyre pressure warning isn't on during the MOT it would pass. The fracture caused a small amount of leakage so the warning light didn't come on for a couple of days. I'm positive that they knew and simply pumped the tyre up before the MOT. They day I picked it up I had done another hpi check just incase, all was clear and it was an almost 4 hour drive home in which the car was fine.

It's my only way of commuting so I can't not drive it. I'll get the issues sorted, it's just annoying. Will definitely look into it further. Thanks for your help everyone

 

[B21]

As long as the low tyre pressure warning isn't on during the MOT it would pass. The fracture caused a small amount of leakage so the warning light didn't come on for a couple of days. I'm positive that they knew and simply pumped the tyre up before the MOT. They day I picked it up I had done another hpi check just incase, all was clear and it was an almost 4 hour drive home in which the car was fine.

It's my only way of commuting so I can't not drive it. I'll get the issues sorted, it's just annoying. Will definitely look into it further. Thanks for your help everyone

If the thermostat sensor has failed then the fan won’t be commanded on (or it may be on all the time) ….you can’t run a N20 motor any distance without a proper coolant control…well you can but then it boils over which is why you lost your coolant….

My 55k N20 E89 never needed any coolant ever..until the thermostat sensor failed..then it emptied its guts in 6 miles..

 

[ZenaBN]

That's interesting because when I first discovered it was low I had a mechanic take a look and he said there was no evidence of leakage. It was quite low so he topped it up and said to keep an eye on it. It hasn't come on again since and the little red bobbin is still at the top so I reckon it hadn't been topped up in a long time and when it was 'serviced' it wasn't even checked.

The loud fan is intermittent. It comes on at a normal speed/noise on longer journeys but if I'm just driving 10 mins up the road, by about 8 mins in, out of nowhere it suddenly comes on really loud so I park up and sit there idling and it's still so loud. I open the bonnet and the engine is a normal temperature, not overly hot. As soon as I switch the engine off it stops and when I switch it back on the fan doesn't cone on again immediately. Seems like a sensor not working perhaps but whatever it is brought up that fault code and I just want it diagnosed so I can fix whatever the true issue is.

 

[B21]

Well you have some considered advice ..leave it with you…

 

[ZenaBN]

Appreciate it. Will let you know what happens!

 

[Pondrew]

No it's a second hand car dealership called Williams Motor Company in Crewe. They sold the car to me knowing the NSR alloy had been welded 3 times and had a further 2 fractures. The car was advertised with silver wheels which they sprayed black to cover up curb marks but they did a very poor job. The low tyre pressure warning light came on a couple days after I bought it due to one of the fractures and when I looked back at a video taken of the interior from the viewing I noticed the low tyre pressure warning light was on then too. Oh and they own the MOT station which is where it passed it's MOT with no advisories and had a 'service' the day before I collected it.

Also the low coolant light came on the day after I bought it, turns out it was almost out of coolant, so much for the service! I did a hpi check before I bought it so just hoped it was a genuine car that'd ended up with a rubbish dealership! Now there's this problem with the fan plus there's an occasional grinding metal noise coming from the OSR wheel and although it's had new discs and pads one of the pads is really worn already. I don't want to give the car up, I just want it sorted.

Hi Sarah. There are some alarming sounding issues in that post. It is very, very unlikely that you caused 2 more cracks in a repaired wheel after a couple of days. Even if you did, the wheel must have been weakened by the previous repairs so should have been noted on an MOT test. The whole point of an MOT is to make sure the car is roadworthy and, above all, safe. The OSR wheel grinding, excessive brake pad wear and cracked wheel are safety concerns. The coolant/ fan issue is a serious mechanical concern.
The dealer should be taking the car immediately for repair and offering a courtesy vehicle, as the issues are potentially so serious.
As already said; I don't think you should be driving that car in that state at all.

Quick internet search found this: Williams Motor Company Ltd Mr William Beech only director
Grosvenor MOT station Ltd same only director as above
The Alloy Boy Ltd same only director as above
A holding company owned by the same

Every car they have for sale has this as a headline paragraph Quote

All Williams Motor Company's vehicles are prepared to a very High Standard and are HPI checked and mileage verified. Our vehicles, where required, come with a Williams Motor Company Service Package and a Comprehensive Williams Motor Company Warranty.

It may be of use.

 

[Scubaregs]

Have you reported the problems to the garage?

 

[ZenaBN]

Hello and thanks for your response. I completely agree with your comments!

They replaced the wheel for me under warranty so I now have a complete set which are safe to use, however it took a while for the replacement to arrive and I needed the car so I invested in a set of Veemann's and have put the originals up for sale.

As for the noisey fan and OSR brakes I emailed Williams and told them I wasn't happy and wanted it sorting ASAP. They gave me the go ahead to book it in at my local garage (my Dad works there in fact) so it had new rear discs and pads fitted (Dad found the previous pads had been fitted the wrong way round which is what caused the noise as they were rubbing), it also had a new thermostat fitted.

I've been driving it for a week since having the work done and am pleased to say the issues are now resolved and it is much nicer to drive, I feel safer so I'm really pleased.

Thanks again to everyone for their input. It's nice to know there's a community so helpful and knowledgeable