Alarm

[hoover]

Hi, haven't been here for a while, hope everyone is doing ok. I need to disarm my alarm, it keeps sounding the horn a few minutes into locking the car. I still need to have the car locked so wondered if there is a way to just disconnect something, any thoughts would be appreciated, thanks.

[kdjones2000]

Word of warning: DON'T use the alarm bypass procedure mentioned in Clark's Garage, or you are going to risk melting a wire and starting a car fire.

I believe that someone on this site posted about the correct wiring needed to bypass the later ('86+) car's alarms. Maybe they will chime in....

[Pauld_94S2]

Why don't you see if you can fix you alarm? It is useful and not too complicated.

The false alarm is probably caused by an intermittent failure for one of the mechanical switches that detect the opening of the doors, hood and hatch or trunk (cab). There is also a wire that goes to the radio; make sure that it is taped off if the radio has been replaced.

kdjones2000 is absolutely correct on the alarm bypass, if you should decide to go that way. The alarm module has different harness wiring in the S2 and it WILL result in a melted wire if you follow Clark's Garage's procedure. There are instructions for the later alarm module but you will have to search for them.

[hoover]

Thanks for both replies, especially about the warning! I do hope to fix the issue but until I do------

[dgcantrell]

I could have sworn I had a couple of pictures of the bypass I did on mine and at least a couple of pics of the factory bypass on the others I have. I'll dig them up.

[hoover]

Thanks, there was me thinking it might be a case of just pulling a fuse, a little knowledge is a dangerous thing!

[dgcantrell]

No, you have to jumper a couple of connections on the connector that plugs into the alarm unit. I'll go out now and take some fresh pictures and post them shortly.

[hoover]

Nice one, many thanks!

[dgcantrell]

My apologies for not getting these quicker. Could have sworn I took some reference pictures of the factory jumper setup some time ago. Anyway, the connector on the car that is factory jumpered is buried behind the DME and I didn't feel like fishing it out. However, the one on my daily driver is not as I left it laying above the DME when I put it back together so I snapped a couple or three pics of it. It is jumped exactly the same as the factory method. Just a couple of short lengths of wire with male spade connectors on each end. The 12 gauge wire I used is actually a little beefier than the factory wires so it should be perfectly acceptable. In the Clarks Garage diagram, they have you put the wires in from the back side while leaving the alarm unit connect. Kind of a goofy way to do it if you ask me. I had to eliminate my alarm unit, that I have never ever used in the 24 years I've had the car, was damaged by some water ingress. The battery tray started to leak water in and onto the wiring harness and it flowed right down into the alarm unit pretty much ruining it. I have since removed it. I may not even replace it..








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[hoover]

No apologies necessary, I am very grateful for your time and helpful pictures, thank you!

[hoover]

Just an update on this issue.
In an attempt to find the fault with my Porsche alarm, rather than having it permanently disconnected, decided to reinstate it and try to sort it out. The last two times it has triggered was 5 minutes after it started to rain, haven't noticed this connection in the past but it's quite possible this has been the common cause.
I can't see why rain would cause the alarm to sound as I thought it was triggered by variation in current flow. Does this rain issue sound feasible ?

[dgcantrell]

If it's being triggered by rain, I bet you have leak under the battery tray and the water if running along the wiring directly to the alarm module. The alarm module is positioned to where the plug is on the top and water will run straight into the damned thing. Ask me how I know.

Check for water ingress in the passenger floorboard along the firewall. I've not seen a 944 that hasn't had this problem unless it has been properly addressed before hand. Acidic vapors from the battery will corrode the metal under the battery and cause it to leak into the cabin.

[944 Ecology]

Originally Posted by dgcantrell

If it's being triggered by rain, I bet you have leak under the battery tray and the water if running along the wiring directly to the alarm module. The alarm module is positioned to where the plug is on the top and water will run straight into the damned thing. Ask me how I know.

Check for water ingress in the passenger floorboard along the firewall. I've not seen a 944 that hasn't had this problem unless it has been properly addressed before hand. Acidic vapors from the battery will corrode the metal under the battery and cause it to leak into the cabin.

You can reposition the alarm control unit to where the connector is at the bottom of the unit. I am also a fan of using ziploc bags (with the opening towards the bottom) as an additional impediment to water (learned that from several Audis in the 1980s). Also works well on ECUs.

[hoover]

Right, thanks to you both I will check that out, seems like a distinct possibility.