Hello All I have a 2000 blazer with two issues, I think they may related. First my factory alarm would go of for no reason, this has happened a few times. Now my interior lights will not go off when the door is closed. I have to push in the override button to turn them off and now the alarm will not set. The security light stays on when door is locked, by remote or pressing the lock button. Any ideas?

 

is the wires groudned of is it disconnected and just on and off hitting something that will ground it

 

the alarm is likely connected to the door switch
If the alarm thinks the door is open(light is on) it likely will not arm or it will trigger
I would take a look at the door jam switches and if its an aftermarket alarm where the splice was made for the open door circuit of the alarm

 

Thanks that's what I thought I will check the switches with an om meter. Any idea what it should read?