Alarm beep but no faults listed

[longrowe]

I have a 1998 RoW C2 Coupe, Tiptronic, 3.4L.

 

When I lock the doors manually with key, or electronically with the key, I get the double light flash and a single beep. I ordered a Durametric cable and hooked it up to check the fault. When I checked for Alarm faults, none are listed. If I do not immediately unlock the car after I lock it, I will get random alarms all day. On the durametric, there is no part number listed in the details section for the alarm module. Does this mean the module is bad and needs to be replaced? Is there anything else I can check (given that the durametric shows no faults) to test the alarm module before I head to the OPC?

 

Thanks!

[Richard Hamilton]

A single beep doesn't indicate an alarm fault - it means the system thinks there is an open compartment.  (Door, front/rear lid, centre console compartment, radio contact).

Do you have an aftermarket radio?  If so, it sounds like the alarm wire has been grounded, when it should be insulated.  Is it wet under the left hand seat?  That is where the alarm unit is located, and if it is wet you need to get it out asap, remove the lid, and carefully dry it out.

If there was a fault, it would give you a double-beep.

[RFM]

A single beep is actually no alarm fault but an open zone, lid center console for instance, not properly closed or faulty switch, no OEM radio, etc. Since the car is a ROW check the lift sensor (square box) and siren near the battery for water infiltration.

[RFM]

Richard, you're faster than me.

[longrowe]

I do have a aftermarket radio but the problem started well after the radio install. I do have the dreaded broken oddments lid (repair hinge is in the mail) but like I said, this "open condition" randomly started. Is there any way to check what is not being closed properly? Is it recorded somewhere the durametric cable can access? It is funny, three days in a row I got no beep when I locked the car, then about an hour later, alarm goes off. So I have to go out and silence it. Otherwise, almost every day for the past three weeks I get a beep from the lock. Besides opening and closing every movable door, Is there any way to tell where the "open" is?

 

I thought it was the radio as well. I have tried taping off the alarm wire, connecting it to ground and heavily insulating the bottom of the radio. My car does not have the pressure switch on the side. The CR-31 that I removed a while ago had a small insulated patch on the bottom. I taped off this area pretty heavily and had not problems until recently.

[Richard Hamilton]

Not sure if the Durametric will do it, but a Porsche tester will list the last 10 events that caused the alarm to go off.  It would also show which compartments show as open, which is useful if you have a dodgy microswitch in the doors, or lids.

 

Anywhere near me?  I have a Porsche tester and would happily plug it in for you.

[longrowe]

Unfortunately, I do not think Bahrain is in your neighborhood. I do appreciate the offer though. I may try and find an Indy here that has one.