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Alarm - mystified

I've bought a chinese car alarm. The instructions are in "engrish" and I can't figure out one part of the circuit; there's a relay, which according to the diagram looks like it makes the low-tension connection to the ignition coil when the key is turned to the ACC position. The relay has a yellow wire which connects to a terminal on the alarm, a white, which looks like it might get 12v from the ACC terminal of the key-barrel, and two (thicker) greens. one of these looks like it is meant to connect to the LT on the coil, but the other? No idea. theres a dotted line connecting it to the aforementioned white wire, but that can't be right? Surely the LT on the coil should not be supplied direct from the keyhole on the steering column? I assume the yellow on teh alarm is earthed when the alarm is deactivated, so the 12v from the barrel is then able to close the relay, connecting the two greens together.

Please help!

John

Reply to
JK
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I can't help directly, but I feel your pain. I hate being screwed like that. I can visualize some interesting and costly scenarios as you seek to protect your Mercedes.

Reply to
WasteNotWantNot

Amusing. the car in question is a 12 year old shitbox. The reason I bought the alarm is that scuzbags tried to break in and damaged the lock, such that it now only works via the central locking. The alarm has a hook up to said central locking.

Why does this matter? Because currently I have to escort my 2 year old daughter into the busy road in order to unlock the car and let her in.

We're not in Mercedes territory, but cheers for your valuable and helpful contribution.

John

Reply to
JK

Don't get mad, John. I'm driving a 21 year old vehicle and a six year old. My comment was not meant unkindly. If you can't figure out the wiring and need to guess you could temporarily use a jumper with with a tiny fuse, say 5amps, to avoid some damage. Thieves can obviously get in your car even when locked. How about a cheap kill switch well hidden and leaving the door unlocked? Or you could install a red flashing led on the dash to try and fool thieves. They are not easily deterred though.

Reply to
WasteNotWantNot

It's only the remote locking that interests me really, I think if I install an alarm it will jsut keep going off until I disable it anyway! But I thought the immobilizer bit might as well get connected up. After a lot of thought I've figured it out - the diagram was wrong. The relay takes a switching input from the alarm box, and an earth. The power circuit of the relay goes in series with the ACC 12v to the ignition relay, rather than in the power to the coil.

21 years old - wow! what is it?

John

Reply to
JK

Chevy Malibu wagon with original 229 V6 automatic, never rebuilt. I believe in serious maintenance, but the end can't be too far away. The

6 year old says it's half hers and she wants it in the back yard as a play house.
Reply to
WasteNotWantNot

"WasteNotWantNot" wrote

NOOOOOOO!!!!!! You have to "IROC" that baby! Popular Hot Rodding -> Issues: May 91 - Nov 91

Reply to
MasterBlaster

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