Central locking is driving me nuts!

[525ITONY]

The central locking on my e34 89 is erratic to say the least the first time I lock it it reopens itself the second time I lock it it stays locked! do I just have a car that wants to be driven soo much she re opens herself or has anyone else experianced this phnomenon?

[e34m30SF]

My car does the same...found out that the trunk lock was not sync up. It's the central lock system's way of alerting you that something is not locked.

[Adnan]

My car does the same...found out that the trunk lock was not sync up. It's the central lock system's way of alerting you that something is not locked.

Hi,

Typically, it's a broken wire in the trunk harness. Check the wires that are attached to the left trunk hinge bar, one or more may be broken. They are tricky little devils, as they look just fine until you separate them and wiggle.

I had that happen and sure enough, one broken wire. Soldered it up and the problem has gone away.

Hope that helps,
Adnan

[525ITONY]

Thanks Adnan
ill give it a go I have looked at the trunk harness before and it all seemed ok but like you said they are tricky so I think its gotta be them or the actual lock itself because if I slam the boot hard the central locking works just fine I may just even need to adjust the catch?
Thanks for the help
Tony

[525ITONY]

Thanks mate I think your right ive isolated the problem to be in that area I may have to buy a "new" trunk lock.....

Thanks for the help
Tony

[filip00]

while we're at it, does anyone have a scheme of central locking module? how it's *exactly* working?

[Jehu]

If you live in a cold climate the door lock actuator may be sticking. I have noticed when temps are below 50ish the passenger lock doesn't engage on the first clikc of the remote button. I manualy lock and unlock that door then it and all other locks including the trunk engage properly. Spring thru Fall this is not a problem,only when the temps drop. I do have some broek wires in the trunk harness,found them when my Licence plate bulb failed and replacing the bulb didn't fix it but they're all intact now.

[Ross]

It's likely a door lock actuator not sending the proper signal to the control module. If you hold the key in the lock position for a moment it may remain locked. Works for me.

[pcross]

Here is a re-run of a reply to the same type of problem I posted to a week ago: One of the microswitches in the system is not being read as "closed" by the computer. I had the exact same problem of locking and an immediate unlock. Here's what I found: I visually checked the microswitch in my driver's door (1994 525i) and saw that the constant opening and closing of the door over the years had worn down the contact bar on the switch. It's very easy to see if you eyeball it close in good light. As a temporary fix (which really has become permanent - I'm lazy), I cut a strip from an old, thin plastic card, slipped it over the switch bar and duct-taped it into place. Now when I close the door, the microswitch closes fully and the problem is gone. Observe the driver's door first. It gets the most open/close action over the years. Then check all of the doors for worn-down micro-switch buttons. You'll be surprised at what you find.

[upallnight]

Are you locking the door with the remote? Could be a bad battery in the remote or a bad remote.

[charlie]

how hard/ expensive is it to change the mircoswitch?


Here is a re-run of a reply to the same type of problem I posted to a week ago: One of the microswitches in the system is not being read as "closed" by the computer. I had the exact same problem of locking and an immediate unlock. Here's what I found: I visually checked the microswitch in my driver's door (1994 525i) and saw that the constant opening and closing of the door over the years had worn down the contact bar on the switch. It's very easy to see if you eyeball it close in good light. As a temporary fix (which really has become permanent - I'm lazy), I cut a strip from an old, thin plastic card, slipped it over the switch bar and duct-taped it into place. Now when I close the door, the microswitch closes fully and the problem is gone. Observe the driver's door first. It gets the most open/close action over the years. Then check all of the doors for worn-down micro-switch buttons. You'll be surprised at what you find.