"door open" sensor is triggering alarm

[Leapy]

Hello there

The alarm on our 08 Roomster has kept going off over the last few days.

After checking windows, loose bits inside and so on I realised that the "map-of-the-car" (no idea what this is really called) electronic display on the dash was flashing. It became clear that the system thinks the driver's door is open even when the door is physically closed (and locked). This then triggers the alarm. I am double-pressing the door lock button on the key fob and this appears to be helping but, having said that, the alarm just went off outside I as I compose this post.

I am not sure how to lock the doors without activating the alarm. Double-clicking the fob button (same as using the in-door button) merely turns off the in-car vibration sensors - the alarm will still activate if it thinks the door is open. I can leave the car unlocked but it's not really ideal to leave my car unprotected.

We are really annoying the neighbours (with a young baby) and I would love to fix this myself - I would prefer to avoid the cost of a garage visit if possible.

I assume that the door has a pressure switch somewhere but I cannot find anything obvious. There's a metal tag at the base of the door that fits into a slot below the door sill but that doesn't immediately appear to be relevent. Does anyone have any clues where to start?

Thanks

Leapy

Edited 19 December, 2011 by Leapy

[freelanderman]

Hi,

The door closed sensors are switches built into the door locks themselves, really you need vcds to determine which door is causing the problem.

Tony

[Leapy]

Hello Tony

What is "vcds" - sorry, that's new to me?.

Also, do you happen to know how to lock the doors without the alarm being activated? I am leaving the driver's door unlocked at present which isn't ideal.

Leapy

[freelanderman]

Hi,

Vcds is a diagnostic program you can run on a laptop, it allows you to check many functions on the car thro the diagnostic socket. The good thing about the Roomster is that you can get away with using vcds lite which is a free download from Ross Tech, you would need a cable to connect between laptop and car, these are available from Gendan for £20.

With this it allows you to check many things including which door is causing the problem.

Removing fuse number 54 should stop the alarm working.

Tony

[Leapy]

Tony

Many thanks for replying again so rapidly. I need to explore Vcds further.

Thanks also for the tip regarding the alarm fuse. That's certainly going to help tonight.

Leapy

[bryanb]

I don't want to hijack the thread, but would like to know if vcds is also useful for a 10 plate Roomster,

Thanks, Bryan.

[freelanderman]

Hi Brian,

I find vcds very usefull but I do all of my own servicing abd repairs

Tony

[neptel]

Have same issue with an 08 Roomster - alarm off 5 times last night - problem exactly as you describe.

Dealer has quoted for a new door locking control unit @ approx £220

Car done a little over 20k.

Does this seem reasonable - asked about fuse to stop alarm - 'I know nothing about that'

Would welcome any advice. Is this an issue with other roomsters ?

[dieselV6]

Issue is age old VWGroup quality problem, present at least since mk4 Golf / Octavia.

The door microswitches are of very poor quality.

Not much can be done after they fail, other than replace the switches yourself or the whole lock by dealer/mechanic.

But at least on the Mk1 Octy, door light current actually flowed through the switch, so to delay switch failure, you could reduce current load on the switch by using LEDs in place of bulbs for under-door light (not present in Roomster) and for interior lighting.

Edited 1 March, 2012 by dieselV6

[neptel]

Sorry two bits of info not included -

First female, non techy, dumb brunettet who doesn't believe it's reasonable for this problem with just 23K miles on a car that's only 3 years old.! Merchantable quality and all that.

Second key has stopped bleeping when car is locked, though it bleeps to unlock it.

Is door locking control unit a part which controls whole car (as I expect) or is there one for each door making 5 in total in the car ?

[dieselV6]

In VW cars, the switches are part of each door lock.

Door locking control unit probably is the "brain" that controls all doors. But it may not be the problem, the problem may be the small switches in the actual door lock in driver door. Usually, wires leading to these switches corrode over time and eventually fail.

Garages frequently quote repair for the most expensive part they can find related to the fault (a classic is replacing injection pump on diesels for hard starting problems, when just glow plugs need to be renewed). Most likely door interior needs to come off and then either entire lock replaced or microswitch connections soldered. Failure of central locking control unit is far less likely. Sometimes the fix is as simple as unplugging and plugging back the door lock electrical connection at either door side or control unit side.

My advice is to seek second opinion at an independend VW/Skoda specialist garage and do not tell the 2nd garage what the 1st one said.

[Tech1e]

First on a Roomster I'd check the door wiring loom. Unclip the rubber boot in the door shut from the top and pull back and check the wires, might well find one or more is broken, pretty common one that.

[neptel]

Thanks so much for this advice. Really appreciate your time and help guys.

[Leapy]

For what it's worth, my door has fixed itself. No idea why.

My daily commute is two hours each way by rail and I had to work out how to leave the car secure without the alarm going off annoying the neighbours.

In order to stop the alarm going off:

a) Enter car from the front passenger door

Flick the manual lock near the gear lever

c) Shut the passenger door.

d) Do not touch the key fob.

e) All doors are now completely locked with alarm not set.

After a couple of noisy weekends (while testing) the error just went away and I have had no problem for over six weeks. I suspect it may have been something to do with the bad weather.

Cheers

L

Edited 6 March, 2012 by Leapy

[shadow2]

Our Roomster has just come back from 4 days at a dealer and previously 2 days at a local garage we've used for 20 years. Between me, the local garage and the dealer we found the following issues.

1. Door open light on when all doors shut.

2. The glovebox light was permanently on.

3. There was a internal earth fault in the electric window motor ! (This turned out to be the cause of the door open warning light coming on).

The glovebox light I found by using my phone's videos function. This was caused by an earth wire behind the stereo coming out if it's connector and touching metal making the light and stereo permanently on(stereo display didn't come on). Once both above fixed all appears to be back to normal and all tests and diagnostics as they should be.

Hope this helps all of you with the same problem.