hi all
my passenger door lock stopped locking a few weeks back (it unlocks fine). after reading some info on here i did a soft reset (disconnect earth on the battery) and reconnected. the lock worked for a few more days after this reset, but then stopped locking - it opens fine on the key and the keyfob button.

now the boot (trunk) has stopped unlocking. it wont unlock on the keyfob button or the button on the dash. when i use the button on the keyfob i can hear a little knock from the boot, so it sounds like somthing is happening in there. i'm having to unlock with the key

might these 2 things be connected? the battery is about 7 years old - ive read a weak battery can cause little electric issues. although the car starts up absolutely fine so the battery isnt affecting the starter motor....

car is 2003 xj6 sport.

cheers...

 

Hi nerf,

Yes a weak battery can cause all sorts of electrical niggles.

On the subject of the boot, that might not be related. The struts can begin to fail and when the boot is unlocked with the button on the fob or on the dash it does not automatically pop up enough to allow it to then open the boot. It basically unlocks, does not lift high enough and then drops slightly, engages and relocks the boot. To check you can do the following. If you shut the boot and then pull up gently on the boot whilst pressing the boot release button on the fob, does the boot then open? If so it's probably the struts failing. I had this on my car.

When you try to unlock the doors from the fob do any of the doors unlock? Or do none of the doors unlock?

Cheers,

Chris

 

thanks for your reply Chris.
i tested your suggestion regarding the boot and it didnt open im afraid. its no longer making the little knock either, so sounds completely dead.

i tried another reset, this time touching the earth terminal against the live terminal - i think this is a hard reset? anyway, this made no difference to the boot but the passeneger door now locks and unlocks.

previously all the doors unlocked and locked, but the passenger door would unlock, but not lock.

cheers
dani

 

Hi Dani,

Ok, at least that rules out the struts as a problem for the boot.

I'd put a battery charger on the car and see if the locks then work whilst on charge. If they work then you know it's battery related. If not then I'd see if there are any fault codes being registered which might give you a clue to then work out where the problem is.

Cheers,

Chris

 

Hi Dani,

Some extra info off the top of my head. The door actuators can dry out and get sticky resulting in random functionality. The microswitches in the actuators can become faulty and then eventually fail completely. However, this doesn't suddenly happen on many doors at once which is why this sounds more electrical supply related.

Thanks,

Chris

 

thanks Chris.
i just tried the spare key fob too... just in case!

 

It seems that you may need to replace the boot actuator-they have a limited life.

Also the passenger door actuator is probably 'on the way out'.