alarm & lock trouble

targa89 · 02-04-2003, 10:49 AM

Well after 2.5 years of lurking on this list...I have crossed a problem of which I can't find an ans. I have a 89 targa which will lock and arm itself at random. The clues to this are..Both door micro-switchs test fine (lock and un-lock the door) However, the center lock buttom will only lock and not un-lock. I am leanimg towards a short (happens most often over bumps) The added bonus to this is that the later year cars also arm themselfs in the locked position...the treat is that the car does not dis-arm in the un-lock position and proceeds to smash to serenity of my neighbors only to contribute to the"prick-in-a-porsche syndrome" P.s. I would like to apologize to the driver of the Blue-grey metalic Cab. heading N.405 sunday after Dunkels...when you tooted you horn I thought it was the alarm again and I was about to push my head thru the windshield!

Jeff · 02-04-2003, 11:44 AM

Targa89, Welcome to the board

.

Does the alarm arm itself when you hit a bump? Does the car stall when this happens?

My interior button on the console locks the doors but doesn't unlock the doors, never has.

targa89 · 02-04-2003, 12:35 PM

Jeff,

Thanks for the wecome (I bought the car because of this board..kind of a DYI guy) The center lock would both lock and unlock the doors. Now here is the thing...if you were to open the door when the car is running it will not stall but the alarm will sound. If the car is not running and the door is opened the full anti-theft mode kicks in DME shut-down ect.On the 89 the alarm is always activated when the car is locked. I believe that the problem lies in the central locking system because of the random locking over bumps ect. I spent superbowl eve giving the "red ass" to the patrons of Motel 6 (San Luis Obisbo) man is that one loud horn! Nothing I mean nothing says Jerk more than a spot-less porsche in a Motel 6 parking lot with an over active car alarm...well maybe I could have taken two parking spots or maybe a Handycap spot...Needless to say I did not sleep for fear that someone would seek revenge. Thanks again

Jeff · 02-04-2003, 01:32 PM

Yeah, Mostly alarms seem to just tick people off, not protect your car.

There is a black wire that goes to the DME relay from the alarm. Mine was armed fully when a bent metal plate, on the bottom of the seat, cut that wire. I ended up by-passing the alarm (I didn't have the key to the alarm) so the car would run. I'm wondering if when you hit a bump yours is doing something similar.

I have the wiring diagrams for your car if you need to know what wire does what. If you don't have the alarm key I think you can get one from the Porsche dealer, you'll need proof of ownership and vin#. If you want to by-pass it I can help with that.

Let me know what you find.

targa89 · 02-04-2003, 02:46 PM

Jeff,

Thanks...I have the wiring diagrams I guess I will spend sometime looking at them. I believe that the 89 and maybe the 88 years don't have an alarm key (armed by the center lock) You have mentioned bypassing the alarm...How? and will this allow me drive home in a pinch! thanks again!!

Jeff · 02-05-2003, 06:53 AM

Targa,

Yes it will let you drive the car but you have to remove the fresh air blower in the trunk to get to the alarm system. It's not a hard job but, it's not a quick job either.

Here is what I did...

1. Remove the negative battery cable.
2. Remove the fresh air handler in the front trunk.
3. Looking into the trunk, the alarm module will be on the left side of the car. Mine had 10 wires coming from it, but it looks like yours may have 12.
4. Find the blue and blue/red wires leaving the unit. They are located in the #61 terminals. Cut these wires and connect the ends that lead away from the alarm (make a good permenant connection, you don't want to have to take the air handler out again). Cap off the ends at the alarm module.
5. Cut the black wire leaving the alarm module. It is in terminal 87A. Cap off the end at the alarm module. Connect the end leading away from the module to another piece of wire and connect that to the bottom of the #8 fuse (which is actually the 11th one back, counting from rear of car to front).
6. Reconnect negative cable on battery and start the car.
7. If you want to put a manual "kill switch" in, install an in-line toggle switch on the black wire before the fuse box.

I hope this helps. Let me know.

Jeff · 02-05-2003, 07:07 AM

Targa, In the Bentley manual they state that the actual alarm system control switch is located in the driver's and passenger's door handle, not the button on the center console. I still think I would start with the one on the console as that one is easiest to get to.

targa89 · 02-05-2003, 09:09 AM

Thanks Jeff...something to do this weekend!

Paul