Front doors would not unlock.

[Ewankinch]

Hi. I'm new to the forum. I have a 8.5 gti and today the front doors would not unlock. I have keyless entry activated and it didn't unlock when I pulled the handle. I tried unlocking with the fob but that didn't work either. The boot unlocked and so did both back doors. 20 mins later it opened as normal no problem. Has anyone experienced this before. Thanks in advance.

[Ewankinch]

Update. I didn't use the Golf today because I would of been late for work it was my partner that was able to unlock it 20 mins later. I've now come home from work and it unlocks OK but it's says on the dash 12v battery low. I put my multi meter on it and it's reading 11.8.volts. This must be the problem so I have put it on charge. The battery is either dud or something is draining it. I'm going to get it booked into the dealers. Hopefully it just needs a new battery.

[sipj]

Interesting that you mention the battery.  I have not had unlocking issues, but have had messages saying to start the engine to charge the battery and also when I have stopped, the car immediately turning off the ignition with a message to save the battery.  The start/stop is also not working most of the time.  Going to call VW and ask them to test it and probably have to go through the hassle of them threatening to charge me if they do not find anything.  I do have a photo evidence though of it happening.

[JoeGTI]

The low 12V battery thing is quite common I think, I used to see it from time to time in my MK8 and I've seen it a few times in my new 8.5.  I think it's most likely to happen if the car's been sitting undriven for a while or if you use the radio for an extended period of time with the ignition off (e.g. when washing the car).
 
And when it is low, I would expect some things to temporarily not work, such as keyless or the leaving-home lights. But I'd still expect it to work via the key fob, thats not good.

[DSGboy]

CTEK MX05 is your friend when owning  performance VW.  COMES WITH A 5year warranty.  I’ve used one on my R which does very low miles, to keep the Battery in shape. Still on original battery at age 6years past March - the CTEK packed up first.  Developed a fault in year 4.   CTEK replaced it with a new one. 😀

[Ewankinch]

Thanks for the replies people. The car is used most days. I drove the car 26 miles round trip to and from work the previous day before the problem so it should of had plenty charge in it. Then 12 hours later when I returned from work after not using it because of the problem thats when the battery was reading the 11.8 volts so definitely something not right. I charged it last night and it's been fine. I checked the voltage tonight and it was 12.4 volts after my journey home that was 13 miles. I'm booked in for Monday to get it checked. I have a ctek 5 amp charger and agree they are good chargers.

[Skyered]

Interestingly something happened to my drivers door and in this case the warning was door open when it was shut. Couldn't drive as a result. Tried everything and then the fault cleared by unlocking/locking with fob - you could hear the difference in noise as the door lock started working. This has only happened once in 6 months 8.5 gti.

[jme63]

Happened to me a couple of times and had to use the key fob button  to unlock it and it also resets the long term mileage as well.

Out of interest anyone know if the 12v battery is an EFB or AGM, need to know whether to set smart charger to standard 12V or AGM setting?  I can't see the top of the battery thanks to the cover which houses  a terminal connection assembly mounted on the front side of the battery.  I suspect with VW's cost cutting, it's an EFB battery -  I think they are a little cheaper.

[Ewankinch]

So it's not just me then. I cancelled my booking with vw as the car has been unlocking ok and didn't want to possibly be charged for diagnostics if they couldn't find a fault. But I Have now turned keyless off as I'm not that keen on it. I don't mind using the fob. At the weekend the car had sat for 2 days and I checked the voltage with my multimeter and it was 12.1 volts which is only 50% charged. Is this normal? Can anyone else check the voltage of their batteries please? I'm sure they are efb batteries  that are fitted. In mk7's they were agm and the 7.5's were efb.