I have a 2000 Volvo C70 Coupe. The sensor in my trunk latch assembly has started to show the the trunk is open when it is actually latched. I triggered the latch with the trunk open and wiggled all the wires in the trunk door and couldn't find a short in the wire harness so I'm thinking the micro switches in the actual latch are starting to go. I'll open up the latch and try pressing the micro-switches more than the cams that actuate them to see if that is the problem too. If so, I'll replace the latch assembly. I do have the following questions:

1. What does the arm from the trunk latch assembly to what looks like a torsion spring do? Does it reset the auto-unlock? - OK, I figured this out. This is for the external key lock mechanism and the rod triggers the solenoid to release the latch.

2. Are the trunk latch state and the car alarm connected? The trunk sensor has been showing the trunk is open more than not lately and the alarm has started to be triggered for no reason the last couple of days. Can this be related?

3. If alarm isn't related to the trunk latch sensor, how do you debug the car alarm?

UPDATE: Last night I noticed that when my car alarm was off the LED light was flashing very quickly (I assume this is to warn me there is an issue). This morning I drove the car and noticed that the trunk open light was mostly off during my drive (most likely because the low temperature this morning). When I parked my car the trunk light was off and I noticed that the alarm light wasn't flashing any more. I set the alarm and things might be behaving. So do you think my alarm issue is related to the trunk latch or the dreaded alarm battery issue?

UPDATE 2: The micro switches seem to be operating find. I also discovered that the metal rod that goes to the torsion spring is the key lock release mechanism (sometimes it is good to look on the other side of what you are working on!).

 

My 98 C70 HT had same problem caused by trunk release button in driver's door.