What's the first steps to figuring out what is going on?

I opened the car today with the key and the alarm went off. I shut all the doors, locked it and it still kept going off. It then stopped all of a sudden....started the car and it went off again.

This went on and on so I pulled the plug on the module under the passenger seat.

Any ideas where to look?

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

Most likely the ATA control unit that you unplugged.

If you can find a good used one...

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Thanks MB Doc.

Do you know if the wagon uses the same module as the sedan?
I guess also I can give a shot at a little solder reflowing...nothing to lose right...

A little embarrassing taking a new girl I just met home and have the alarm going off for 10mins before I could figure out what to do. I think my wagon was giving me a sign...

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

you might also make sure it isn't just the little alarm switch on the door handle tumbler. on my '87TD the driver's door will not disable the alarm. you must open the car from the passenger door or the tailgate. in other words in our car if you lock the car then unlock with the key at the driver's door, the alarm will do off and the only way to turn off the triggered alarm is to lock then unlock again from the passenger door or tailgate.

we've gotten around this with a keyless entry installed so we just never use the key to unlock the car.

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punkinfair

i agree with punkinfair, there are microswitches in each door, which can be reached without removing the door cards/interior panels

i experienced the same problem.

tip: if your TE has the little led light on the dash which flashes when the alarm is engaged, try unlocking the car from a different door : either the trunk or passenger side door and then check to see if the light is still flashing. if it is no longer flashing then its safe to get in

goodluck