Alarm activation

[comfort zone]

I have a 1997 E300 diesel estate. The alarm keeps setting it's self off for no apparant reason. It started yesterday about 8pm, again at 5am and 5-30am.
It was ok all day untill about 8-30pm this evening, then it went off again!
The car has interior motion sensors and tow away protection.
I have checked everything I am able to check, lights going off and closing air vents, but that doesn't seem to have made any difference.
Could a moth or fly inside the car have set it off? Is there some way that a main dealer can trace the cause electronicaly?
Your ideas and thoughts would be appreciated. Thanks.
Quick before the neighbours get really pi*sed off!

 

[Blobcat]

Water in door / bonnet / boot switches?

 

[Ron Palfrey]

If it is annoying your neighbours why not lift your bonnet, find the siren and unplug it. At least it'll stop the noise while you identify the cause of the alarm going off.

Once sorted just plug the lead back into the siren again.

Ron

 

[comfort zone]

I don't think the neighbours are that pi*sed off yet!

 

[pcman_jh]

My 1999 E300 DT suffered the same problem. After reading about it on these forums it all pointed to a hyper sensitive internal motion detector (or heat sensor). The advice given was to disable the internal monitor (you should have a switch on the dash, meant for dogs etc) just leaving the door and bonnet detection active. I've not had a problem since and that's now been a month. It's just a case of getting into the habit of hitting the dash switch every time I leave the car overnight.

The problem can be triggered by air currents in the car, the system is that sensitive with no obvious signs of adjustment. The articles also talk about closing off your air vents on a windy day as cold air being blown into a hot interior is enough to fool it into action!!!

 

[Blobcat]

My 1999 E300 DT suffered the same problem. After reading about it on these forums it all pointed to a hyper sensitive internal motion detector (or heat sensor). The advice given was to disable the internal monitor (you should have a switch on the dash, meant for dogs etc) just leaving the door and bonnet detection active. I've not had a problem since and that's now been a month. It's just a case of getting into the habit of hitting the dash switch every time I leave the car overnight.

The problem can be triggered by air currents in the car, the system is that sensitive with no obvious signs of adjustment. The articles also talk about closing off your air vents on a windy day as cold air being blown into a hot interior is enough to fool it into action!!!

It's always nice to see advice working out.

 

[comfort zone]

My 1999 E300 DT suffered the same problem. After reading about it on these forums it all pointed to a hyper sensitive internal motion detector (or heat sensor). The advice given was to disable the internal monitor (you should have a switch on the dash, meant for dogs etc) just leaving the door and bonnet detection active. I've not had a problem since and that's now been a month. It's just a case of getting into the habit of hitting the dash switch every time I leave the car overnight.

The problem can be triggered by air currents in the car, the system is that sensitive with no obvious signs of adjustment. The articles also talk about closing off your air vents on a windy day as cold air being blown into a hot interior is enough to fool it into action!!!

After I posted last night I closed the vents where possible and checked the interior lights were operating correctly, including the rear. I dusted around the internal sensors (on door pillars I believe) and made sure all the doors and tailgate were closing properly. I found no faults, but I got a good nights sleep, and fingers Xed, it has been ok since!
It is good to see simple advice given on here working.

As an extra, can you tell me how or where I can get a workshop manual for this model as Haynes don't seem to do one?:wink:

 

[pcman_jh]

Manual for the E300

I used to have a C250 Diesel. Just after getting my E300 diesel I soon realised they shared a lot of the engine and drive train components. My solution was to buy the C Class Haynes manual as the E300 engine is just a 6 cylinder version of the C250 diesel's 5 cylinder engine, which is covered in the C Class manual! Hey presto!!

PS - Haynes has the E Class manual 'under consideration' which means they're thinking about it!

 

[comfort zone]

I used to have a C250 Diesel. Just after getting my E300 diesel I soon realised they shared a lot of the engine and drive train components. My solution was to buy the C Class Haynes manual as the E300 engine is just a 6 cylinder version of the C250 diesel's 5 cylinder engine, which is covered in the C Class manual! Hey presto!!

PS - Haynes has the E Class manual 'under consideration' which means they're thinking about it!

Yeah, thats not a bad idea with the Haynes manual.
About 4 years ago I owned a Jeep Cherokee Diesel and Haynes had that "under consideration", I think they still have! I got over that by buying Chilton manuals as Chilton do one for the Jeep, with the VM engine.
Ps. The Alarm has been quiet for the last two nights.

 

[OlafMaxwell]

I bet that VM diesel engine gave you plenty of work.........

 

[comfort zone]

I bet that VM diesel engine gave you plenty of work.........

It was very good untill the weather got cold. One freezing February morning I drove down the hill from my drive, which was no effort for the old engine. As I put my foot down to climb the hill there was a loud bang followed by a misfire. I managed to turn her round and limped home very noisily and with a lot of smoke. I investigated and found a pushrod had jumped out. Put it back in easily enough and all was ok untill the next cold morning when exactly the same thing happened. I put it back again and consulted my mechanic. He suggested I either got rid of it or had the engine stripped as there was probably an oil blockage to a cam follower! It had to go before a pushrod got bent and caused a lot of damage.
Why they ever used an Italian engine that was built to run generators, in an American vehicle, I dont know. I understand they were also used in Rovers!
Obviously a cheap job lot!!

 

[Tom Chignell]

Getting back to the original point, if I may. I have Viano people mover which has the same problem with its motion detector. I have noticed that it goes off at the end of the day and seldom at other times - so that would probably align with the cold air theory above. Not very practical to shut vents every day and pretty annoying to have to turn the motion detector off. Can't it be calibrated somehow?
Thanks

 

[dragon]

.................or a spider.