Hey all,

Having a bazar alarm door lock issue in my 04 coupe. When driving the doors lock and unlock randomly. What's also happening when the car is off, locked, the doors will randomly unlock themselves causing the alarm to go off. So we cannot park the car locked until I figure out WTF. Any ideas?

All comments welcomed, comedic included.

Cheers, Mike

 

Years ago when the factory battery in my wife's 2006 XK8 began to weaken, the car alarm would sometimes go off by itself and the trunk lid would sometimes pop open by itself. Replacing the battery immediately fixed those issues....

You could also have a failing microswitch in one of the door's latch assembly....

 

Batteries can cause faults!!!!!!!!!!!!
Several modules with BATTERY VOLTAGE LOW faults might be the cause?

Find someone with dealer level diagnostics (WDS/IDS) and interrogate modules for LAST ALARM ACTIVATION report.

The body closure switch for the 'offending' opening will help with the diagnosis.

 

Thank you guys for the replies. I will be chasing this today.
Cheers, Mike

 

Get crazier. The car today sitting, using my meter not the gauge is 12.56V off. When running it bumps up into 14VDC. Watching the voltage when I lock the car there is a quick drop then levels out back to 12Vsih. Today the car when locked beeps, alarm armed and within seconds unlocks the doors and the alarm goes off.

Played with locking the car when running and it unlock after a few seconds. Today it unlocked then relocked when running. I used the handle to lock while running at a standstill to eliminate any speed sensor freaky stuff. Bazar. During all of it the volage has been solid. Si I am assuming nothing straight to ground in the handle. Maybe not. It's goofy. I am going to find and pull the alarm fuse and see if the doors keep locking and unlocking. Then maybe pull the electric lock relay and manually with the key lock the door to see what the alarm does.

Any thoughts welcomed.
Cheers, Mike

 

Still lost

 

Disconnect the battery for while then try again
​​​​​​

 

Did a hard reset of the system. Unhooked battery and connected the leads and head for a few minutes to drain capacitors etc. Had the car on charger for battery just incase and all was good. No more acting funny until three days went by. Doing same thing again. Checked the aftermarket PO installed radio and no drain while the car is off so not it. Not sure if anything is draining the battery while parked. It starts right up just is not happy. Im going to start pulling circuits out of service to see if anything changes by removing fuses while parked.

Any ideas, thoughts or comedic remarks appreciated. The battery is only 9 months old.

Cheers, Mike