Oddball interior buzzer/alarm???
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Joined: Nov 2019
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e320
Oddball interior buzzer/alarm???
I have a 2007 e320. About once per week after I open a door a very high pitched alarm or buzzer sounds for between 20 seconds and 2 minutes. It’s loud but NOT projecting outside the car. So I don’t think it’s an anti theft alarm. Putting in the key and turning on the car does not stop it. Pushing key fob buttons does not stop it. It eventually goes out by itself. But it’s pretty annoying. I don’t think it’s parktronic but I’m going to test that system (probably remove fuse). It seems to come from under the driver dash. Like near the foot brake. But it’s very hard to locate. And I cannot make it repeat on my schedule. I removed the head unit and it’s not that. Ideas???
PS I should add that (1) the head unit died recently and I replaced it with a modern android unit (working well), and (2) the first time the buzzer / alarm sounded was when I removed the cover panel above the drivers foot pedals (running gps/antenna wires to the trunk). It’s a different sound than the emergency brake makes when left on. Is there some kind of tamper alarm related to that foot panel?
PS I should add that (1) the head unit died recently and I replaced it with a modern android unit (working well), and (2) the first time the buzzer / alarm sounded was when I removed the cover panel above the drivers foot pedals (running gps/antenna wires to the trunk). It’s a different sound than the emergency brake makes when left on. Is there some kind of tamper alarm related to that foot panel?
Last edited by flbiggs; Mar 30, 2023 at 07:47 AM.
Thread Starter
Junior Member
Joined: Nov 2019
Posts: 25
Likes: 3
e320
Update…I traced the problem to the optical decoder box used to tie the pre amp outs on the android head unit into the most system. It usually sounds pristine but seems to flake out on occasion. I’m thinking there’s a ground loop issue and I’m going to add an isolator to the rca cables. I’ll report back with success or failure.
