Door Lock Troubleshooting Help

[UsernaM3]

Alrighty dudes and dudettes,

With the key fob I have the driver's side door doesn't unlock or lock. If I manually turn it with the key in the door it works fine, but the fob doesn't work, passenger and trunk unlock and lock just fine though. Where should I start with this guy? Something in the door or is this going to be more security system / electrical?

[ArcticM]

Have you replaced/checked the door lock actuator?

[UsernaM3]

Not yet! I wanted to see if anyone has any more info first as I am not sure how the lock actually works. This was my thought process: maybe manually unlocking or locking with the key in the door just electronically activates the same motor, in which case the motor would've been fine? Does that make sense? lol. I didn't want to just throwing parts at it if it wouldn't change anything

[ArcticM]

Pull the door card off pop the actuator out and visually observe if the actuarors working. That’s typically what will fail in the locking system. Especially with what you’re describing

[TostitoBandito]

It's the actuator. When it fails, usually on the driver's door, the symptom is that the "power" lock function no longer works at all on that door. Meaning that if you put a key in the driver's door the lock works fine, but the door won't lock or unlock when you operate any other lock on the car, or when you hit the lock/unlock buttons in the car.

[UsernaM3]

Y’all are great! I’ll see if I can get a new actuator from a friend at the dealership (good to have friends in high places, right?)

ill keep everyone posted on how it goes.

[TostitoBandito]

You can also order them from any number of places online:

https://www.fcpeuro.com/products?utf...%0967111387726

The genuine BMW part is around $130-150, and the cheaper Siemens/VDO OEM part is around $55-60. I got the VDO part when I did mine since the difference in price was so large. Seems to work fine.