Alarm Help
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Joined: Nov 2004
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
Alarm Help
hey. i have a 1986 300E. i have the factory alarm. but it's not working properly. when i lock the doors with the keys it honks from the secondary horn (near the ABS). it has never gone off nor am i able to set it off. i can lock the doors and open the door from the inside, but all it does is honk once. nothing else. no flashing lights..nothing.
i was messing around with the fuses today and i took out the fuse that controls the doors and some other accessories. i tried to arm it. it honked as normal but when i try to set it off all i get is a VERY low honking with the flashing lights. as it would normally be. but the horn is VERY quiet.
here are some pics of underneath the passengers side carpet:
here are some videos of what it does.
Arming with the fuse in
http://Home.comcast.net/~Nick_M_51988/armfuse.MPG
Arming with no fuse in.
http://Home.comcast.net/~Nick_M_51988/armnofuse.MPG
What might be the problem here?
i was messing around with the fuses today and i took out the fuse that controls the doors and some other accessories. i tried to arm it. it honked as normal but when i try to set it off all i get is a VERY low honking with the flashing lights. as it would normally be. but the horn is VERY quiet.
here are some pics of underneath the passengers side carpet:
here are some videos of what it does.
Arming with the fuse in
http://Home.comcast.net/~Nick_M_51988/armfuse.MPG
Arming with no fuse in.
http://Home.comcast.net/~Nick_M_51988/armnofuse.MPG
What might be the problem here?
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Joined: Oct 2004
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From: Eastern Washington
1991 300E
Have you ever done anything to the stock stereo Head Unit? The HU has a connector on it from the alarm, where if the HU is pulled out, it disconnects the alarm lead and sets the alarm off. That lead has so be grounded to the radio chasis. I found this out when I replaced my HU with a Blaupunkt model. Luckily the Blaupunkt chasis had a tab on it to connect the alarm lead, and that solved my problem, which was very much like yours, the alarm goes off if you lock the doors with the key. (Incidently, that is the only way to arm the alarm, with the key from outside the car.)
Thread Starter
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Joined: Nov 2004
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
what does this wire look like?
because i do have an aftermarket system. the mokeys at circuit city put it in. when i bought the car there was no radio period.
because i do have an aftermarket system. the mokeys at circuit city put it in. when i bought the car there was no radio period.
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Joined: Oct 2004
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From: Eastern Washington
1991 300E
Don't remember off the top of my head. It had a rectangular female connector for a male spade on the radio, with a spring 'hook' that hooked onto the dash cutout that the radio goes into. You hook the wire up with the radio out of the dash, then after you slide the radio into the dash it hooks onto the dash and thus if the radio is pulled out it disconnects the wire. Sounds like your problem though. I can't remember if the wire was brown or black colored. Actually I can't remember the color at all, and I don't remember seeing it in the factory wiring schematic. Basically I think that the signal it sends the alarm is a ground when 'all is well', and a loss of ground if the radio is removed with the alarm turned on.
Circuit City? There is your problem right there.
Good luck
Circuit City? There is your problem right there.
Good luck
Thread Starter
Member
Joined: Nov 2004
Posts: 123
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
isnt it knida odd that the alarm only goes off (horn honks) when the fuse is out? when the fuse is in everything acts normal, aside from not going off.
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Joined: Oct 2004
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From: Eastern Washington
1991 300E
Originally Posted by Nick_M_51988
isnt it knida odd that the alarm only goes off (horn honks) when the fuse is out? when the fuse is in everything acts normal, aside from not going off.
I'm not sure what other things the alarm is hooked into, I just know the trunk, doors, hood, and radio for sure.
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