1997 Mercury Mountaineer
Miles: 180,000. Transmission: Automatic 5 speed. OBD scanner showed "PASS", no code found.
Hello everyone
The Mercury ran great the day before I uploaded this post and now it's acting very strange. When opening the driver door (including any door, even the hood) the anti-theft alarm would go off (all doors are in an unlocked state). Normally when turning the key to the "ON" position it would turn the alarm off.
Unfortunately not only did the alarm stay active, the SUV would no longer start. As if no power is going to the starter (which was replaced recently). Alarm did turn off by itself nearly 10 mins. (I pull the plug off the horn so it would stop blasting my ears)
With the key in the "ON" position I do hear the fuel pump priming, lights on the cluster gauge coming on as normal, relays clicking, and all fuses check good.
My guess the computer or ignition switch somehow shorted, or a short to ground somewhere. I never encountered this type of problem before so this is very interesting on what causing the alarm to go off and why the engine won't turn over.
Well, something is triggering the alarm but it can't be some kind of short itself because if there was a short itself the alarm would go off by itself. Not when you open the door. You have some type of alarm problem. You're going to get a a good mechanic to check it out with this fancy scan till the alarm systems on those things were pretty crappy and as they age they can get many problems. And you can't just turn it off. It has to be fixed
@scottykilmer I will have someone take a look at it. Thanks Scotty!
@scottykilmer Update: After doing research about the anti-theft system I learned it can immobilized the ignition switch. The Mercury has a keypad on the driver door so I figured if I put the code in it lets the computer/anti-theft system know the doors are unlocked.
Put the key in and fired right up!
I guess what triggered the anti-theft system is the internal parts on the driver side door handle is worn out (door handle flaps up and down instead of staying flush with the door) and somehow left the anti-theft system armed instead of shutting off when unlocking the door.
Or it could be something else triggering the anti-theft system. Either way this is a problem I need to address, but thank you Scotty on helping me with this matter!