mx5cartalk.com

My 2001 NB has the stock alarm.
Recently I accidentally opened the driver's side door (without unlocking with the keyfob or key), and the alarm went off. Strange as I thought I had locked the car previously with the keyfob. So I did a test:

- locked the car using the keyfob, opened the driver's door using the handle only and the alarm went off. Tested it overnight, same thing.

- after locking the car using the keyfob, I peeked through the windows and noticed that the passenger side door was locked (looking at the lock tab inside), however the driver's side door was unlocked. So that would explain why I was able to open the driver's side door.

So does that sound like a problem with the central locking mechanism, or is some sort of programming of the keyfob/alarm/central locking? How do I do that?

Over the past year or so I've had a battery change, and more recently replaced the battery in the keyfob. The keyfob in each instance seemed to perform as before i.e I could unlock the boot, lock (i thought!)/unlock the car. So I don't know what's happened.

I don't like the idea of no physical security on the car. The alarm going off isn't a real security, just a nuisance for neighbours!
TIA for any comments.

- another test: I was able to lock the driver's side door with the door key. So I suppose that's a workaround if I used the door key first to lock all doors then activate the alarm with the keyfob. Still looking for a solution though just using the keyfob.

Sounds to me like the door lock actuator might have failed.

Simple test to check would be to get down next to the drivers door and put your ear against it. then hit the lock unlock buttons a couple of times and listen for the actuators motor working.
As they get older the motors can weaken to the point where they will work with no load on them (unbolted from the door and in your hand)but do not have enough torque to pull the lock mechanism when installed. As all the plastic piviots get older everything starts to stiffen up just like the electric windows slowing down...

If the motor is functioning but not strong enough to pull the mecanism you can try cleaning and lubing all piviot points and rods to make the lock smoother and lighter to operate but this may only get you another couple of months before it fails again. I would be looking around for a goos 2nd hand replacment.

Rolley.

Rolley wrote:Sounds to me like the door lock actuator might have failed.

Simple test to check would be to get down next to the drivers door and put your ear against it. then hit the lock unlock buttons a couple of times and listen for the actuators motor working.
As they get older the motors can weaken to the point where they will work with no load on them (unbolted from the door and in your hand)but do not have enough torque to pull the lock mechanism when installed. As all the plastic piviots get older everything starts to stiffen up just like the electric windows slowing down...

If the motor is functioning but not strong enough to pull the mecanism you can try cleaning and lubing all piviot points and rods to make the lock smoother and lighter to operate but this may only get you another couple of months before it fails again. I would be looking around for a goos 2nd hand replacment.

Rolley.

Thanks. What you said makes sense, esp with an older car like mine. Are the door trims etc easy enough to remove to clean and lube the locking mechanism?