Josh B

I've searched through the archives on this and found that most folks just bypass the alarm. I would really like to solve this puzzle though.

The car is an 89 turbo. Currently is starts just fine with the alarm box in place. If I roll down the window though and lock the door - then reach in and pull up the lock to unlock it and open the car the alarm does not go off. The part number on the alarm box that was in the car is 928.637.104.03 RDW. According to Sunset what should be in the car is 928.637.104.05 USA. I bought one of those boxes used from Lart and put it in the car and had the same results. Just in case the hood switch wasn't engaging I zip tied it into the closed position and got the same results. Also swapped in a spare alarm relay - do difference.

On top of that and possibly related I can unlock the rear latch from the button up front but it will not unlock via the key in the back. On the later model cars it is not a mechanical lock back there - there is a microswitch that activates the hatch motor. I bought a brand new microswitch and that made no difference. Bought a used hatch motor from Lart and that made no difference either - still only works from the front button. Swapped out the switch up front as it looks like they share some wires and that made no difference.

I printed out the wiring diagrams and tried to trace wires but it is confusing. Looks like the rear hatch microswitch is tied into the alarm system as well. Also the wiring refers to an additional alarm unit and I only know of the one in the passenger foot well.

I opened the alarm boxes up and it looks like some of the traces have lost their silvering - couldn't quote tell with the multimeter if that was causing problems or not as there is a coating over the back of the board. I went out on ebay and bought two more alarm units to try out over the weekend but they haven't gotten here yet.

running_cold924

it's an enigma, wrapped in a conundrum, and stuffed INTO a puzzle. Good luck Josh, would like to see you figure this out. sorry I'm not any help but from all the 944's I've had, I never got a key for the alarm system and never pursued it any further.

I'll be watching though...

dillon410021

same here

AScholtes

Sounds like there is a short somewhere to me. If the traces were burnt I would check where those terminate and what input or out put they go to and then trace those to see if there is a short to ground.

brian944turbo

If you can't fix it, I'll buy it. Who needs an alarm anyways.
Just kidding.

Rip It

I would think most alarm problems would be getting it to turn off. All switches need to be closed for it to be disabled. Corrosion (particularly the hood switch) normally causes an open circuit=alarm on. Also u may have mechanically closed the hood switch with a tywrap but it may still have an open circuit. Sounds like your common issue is the alarm siren/horn or it's controller.

gux944

[QUOTE=Josh B;8218621]I've searched through the archives on this and found that most folks just bypass the alarm. I would really like to solve this puzzle though.

The car is an 89 turbo. Currently is starts just fine with the alarm box in place. If I roll down the window though and lock the door - then reach in and pull up the lock to unlock it and open the car the alarm does not go off. The part number on the alarm box that was in the car is 928.637.104.03 RDW. According to Sunset what should be in the car is 928.637.104.05 USA. I bought one of those boxes used from Lart and put it in the car and had the same results. Just in case the hood switch wasn't engaging I zip tied it into the closed position and got the same results. Also swapped in a spare alarm relay - do difference.

On top of that and possibly related I can unlock the rear latch from the button up front but it will not unlock via the key in the back. On the later model cars it is not a mechanical lock back there - there is a microswitch that activates the hatch motor. I bought a brand new microswitch and that made no difference. Bought a used hatch motor from Lart and that made no difference either - still only works from the front button. Swapped out the switch up front as it looks like they share some wires and that made no difference.

I printed out the wiring diagrams and tried to trace wires but it is confusing. Looks like the rear hatch microswitch is tied into the alarm system as well. Also the wiring refers to an additional alarm unit and I only know of the one in the passenger foot well.

I opened the alarm boxes up and it looks like some of the traces have lost their silvering - couldn't quote tell with the multimeter if that was causing problems or not as there is a coating over the back of the board. I went out on ebay and bought two more alarm units to try out over the weekend but they haven't gotten here yet.

[QUOTE]

Can you tell me please where the alarm box is located at?Picture maybe?

Josh B

Hey Gux - alarm unit is mounted in the passenger foot well by the DME.

I have some good news. After a little more research I discovered that a couple of the relays were plugged into the wrong spots. Rectified that and got a relay I was missing from Albert today. Now the rear hatch release works and so does the alarm.

As a result of my troubleshooting I now have three spare late alarm computers and also a working late rear hatch motor and brand new rear hatch microswitch. Let me know if anyone needs them

I was hoping this relay mix up would fix the ABS light problem I am having as well but no dice. Will start another thread about it

AScholtes

Sounds good Josh! PS, I received the covers today

running_cold924

abs light may be the abs relay. fixed a friend of mine's...

PEvans

Josh, how could you tell from the wiring diagram that the hatch switches are tied in to the alarm?

How did you get the footwell hatch switch out?

Do you now understand how the footwell and key switch and hatch motor all work together?

I might be interested in some of your parts.

Justin S2

Can someone please post a picture of where the hood alarm switch is for the alarm? My system has been randomly going off ever since I pulled the engine (which involved removing the hood so I assume it is that.) It could also be the alarm box (had battery box go bad and later a DME), or the hatch switch (since it doesn't always close properly.) I removed the actual horn itself so I can't hear it but I do have people randomly tell me my hazard lights are on.

How much would you like for an alarm box? Is it tested?