2011 XC90 Alarm

[Just Drive]

Thought I would check VIDA about this and I can confirm no coding is necessary for this job. I'm booked in next week for this. Below is an extract of the instructions:

36: Automatic monitoring

Mass movement sensor module (MMS) rear, replacing

Removal

Preparatory work

Deactivate alarm.

Remove:
the panels for the D-posts. See Panel D-post, replacing
the cantrail. See Panel cantrail, replacing
the cover over the screws for the cargo net holder. See the illustration
the screws for the cargo net holder.
Remove the clips for the headlining as illustrated.


Removing the mass movement sensor module (MMS)

Hint:
The sensor is secured to the top of the headlining using double- sided adhesive tape.
Note! When working on the headlining, ensure that there are no creases.
Carefully bend down the headlining. Twist off the sensor. Disconnect the sensor connectors.

Installation
Installing the mass movement sensor module (MMS)
Note! The location of the mass movement sensor module (MMS) is important for the alarm to function. The volume sensor must be installed in the recess to function correctly. The sensor must be installed so that it is straight. It must not be turned more than a maximum of 5°. The connector must be to the right looking forwards in the car.

Connect the connector.

Remove the protective film from the tape. Only use the tape supplied with the sensor.

Press the sensor into place in the top of the headlining using the tape. Press by hand for at least 15 seconds.


Finishing work

Install:
the clips for the headlining
the screws for the cargo net holder
the covers over the screws for the cargo net holder
the cantrail. See Panel cantrail, replacing
the panels for the D-posts. See Panel D-post, replacing .

Test the function.

[rpe2]

Many Thanks.

Sory to be cheeky, but does VIDA give you the part no?

Thanks

Richard

[Just Drive]

VIDA says 'Sensor, rear, MMS, Part No. 30659265.'

[marali]

Hi,

I have an xc90 2010 SE LUX. Since purchasing the car 5 years ago, the car alarm have been miss behaving. Every summer for approx 2 weeks solid, it will randomly go-off regardless of weather condition (hot/cold) and day or night. Recently it is becoming so frequent, the only way to stop this is to enable the low guard function. How do I start to fix this issue? I was thinking of replacing the alarm sensor (mass movement sensor) but have no idea where it is located, and how easy it is to replace this myself. Any advise will be much appreciated. Otherwise it may be an expensive trip to the dealership.

Thanks
Marali

[Moose Test]

Hello.

If enabling Reduced Guard stops the alarm from triggering then I believe you're thinking on the right lines, namely that it is an issue(s) affecting either the tilt sensor or the mass motion sensors.

Are you by any chance leaving any active electronics in the vehicle? I thought that I had an issue with my '07 XC90 when I first purchased it, until I read some posts on this forum and made the connection - the alarm would always trigger after some random period of time had elapsed, if I left my phone switched on inside.

That possibility notwithstanding, you really could use a VIDA diagnostic, which would tell you what the source of the last trigger(s) actually was. Depending on your level of technical skill, you could acquire a VIDA / DICE unit from eBay, or for about the same amount of money, ask your local Volvo dealer or Volvo independent to scan it for you.

The purpose being to determine what is actually at fault, before you start making unguided replacements. The ultrasonic (perhaps microwave, in later years) mass movement sensors are located under the headlining. There are two, one forward (near the interior lights) and one back (about 30cm from the rear top cargo trim). Having replaced a headlining myself recently, I can tell you that this is possible to DIY, if you are feeling brave but it is time consuming and a pain in places. Hence my suggestion that you confirm first what the issue actually is.

[marali]

@Moose Test,

Thanks. I don't normally leave any electrical devices in the car (although I will check). And you are probably right, I should get proper diagnostics and not try cut corners.

I do like DIY challenges, but let get a proper diagnoses before I take everything apart.

[AB-UK]

My Son's remote controlled car can set off my alarm.
2010 XC90 Exec.

[trumpetdropper]

The siren doesn't need coding, just fit and plug in!
I've just replaced my siren with one a bought off this forum, which had had the rechargeable battery replaced - all works fine, no messages etc.

Hope it helps

[DonHS]

Hi
I have several queries/problems with my alarm and I'd love some guidance please. My car has new scuffs on it practically every time I look but the alarm never sounds off but if a loud vehicle drives past then the alarm will sound. Likewise if the windows are open the alarm will sound off if a gnat flies in when I forget to lock up using the key when the dogs are with me. Sometimes I get a message when I start the car saying the alarm has been activated, please check your vehicle but there has not been an audible alarm. The other prob (nuisance really) I caused myself. I went to reset the 'regular service due' and anyway, it still says the same but now my lights don't flash when I lock the car but they do when I unlock it. The thing in the window still flashes as it used to. That's it for now, can't think of anything else I've trashed lately. Oops, 2007 XC90 D5 SE. Many thanks.

[SwissXC90]

Originally Posted by DonHS

I have several queries/problems with my alarm and ...

Time to use VIDA to diagnose the probems