Alarm Problems

Hey guys.
I have a 1990 928 s4. its in good condition.
However, every time I lock the doors to the car and go inside, the alarm would sound 5 minutes later.
Does anyone know what I could do to fix this problem? I'm pretty handy and the more I take apart this car, the more I learn.
Does anyone know where the issue sources from?

-thanks, Jake

The first thing to do is clean all connections in the wiring from the door switches and to the alarm module (light switch) ... a little corrosion could be enough to trick the alarm module to go off.

Connection problems are the cause of 90% of electronics glitches.

Rich
Membership Chairman
Charter Member
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