Freelander 1 Door Locking / CCU

Hi,

When I bought the car a few weeks back one rear side door did not unlock from the fob, but all locked with the fob.
Last week the other rear side door stopped unlocking from the fob, but still locks.
I changed the fob battery yesterday - no difference.
Today I have been playing around with the fob and the interior lock/unlock switch and it seems erratic, but for sure the rear side doors did unlock using this interior switch in some circumstances (I wasn't able to work out exactly under which circumstances tho).

So this must mean that the motors, links, relays etc involved in the rear side doors unlocking must be OK since they did work a few times, and it is very consistent in that they never unlock with the fob?

So I thought it must be in the control side.

After working out that the 'rear fog guard lamp switch' was just the rear fog lamp switch (why 'guard'?) I followed the instructions in RAVE (or here) after making sure all doors were unlocked:

1. Hold the rear fog guard lamp switch on.
2. Turn the ignition off.
3. Turn the ignition on.
4. Release the rear fog guard lamp switch.

But I got no buzzer or interior light pulse.

Am I doing this right - ign. on, press and hold fog light switch (the one to the left of the steering wheel on the side of the instument 'pod'), ign. off, ign. on, release fog light switch? All within 4 seconds. Presumably 'ign. on' means until warning lights come on?

Generally, in normal operation, the things on the CCU test list seem to work, except door locking is incomplete (see above)

The only other thing I have noticed is that when I open the tail gate it unlatches until the door opens a fraction then it catches and I have to lift the handle again to activate the door lock again and then I can open the door (I do always wait for the window to drop a bit before pulling).

Any ideas / advice please?

Unlocking problems using the remote or key can normally traced to the lock motor in the door. There are 2 motors in the lock assembly. 1 does the normal lock and the other the super lock. If the super lock motor fails or goes sluggish, the door won't unlock on fob. This is assuming that single entry mode is isn't set in the CCU.

Nodge68 said:

Unlocking problems using the remote or key can normally traced to the lock motor in the door. There are 2 motors in the lock assembly. 1 does the normal lock and the other the super lock. If the super lock motor fails or goes sluggish, the door won't unlock on fob. This is assuming that single entry mode is isn't set in the CCU.

Click to expand...

OK, I read up on normal and super lock
One fob press gives drivers door open, next press opens passenger door (and should open rear side doors) - does this mean I have single entry?

Bife said:

OK, I read up on normal and super lock
One fob press gives drivers door open, next press opens passenger door (and should open rear side doors) - does this mean I have single entry?

Click to expand...

Yes that's single entry point active, which most seem to be.
Your rear door lock actuator motors aren't working correctly, so just need replacing to return there function.

Hi
An area prone to electrical failure on some cars is where the wiring harness passes from the door frame to the doors and tailgate. Repeated opening/closing weakens the wires and they break - usually the larger wires.

You don't mention what age or model your car is??
If we assume a MK1 Freelander.
To check if it is a lock failure or the problem is elsewhere, once you have removed say the right rear door card, the door lock and wiring are very visible.

With only that door open, manually click around the door latch to the locked position (even though your door is still open, the car will think it's closed)
Then, with a sturdy pin 'back probe' the connector - follow each of the wires in turn to the multi-plug of the lock until it bottoms out. - Connect a volt meter to the pin and press the plipper to lock the car - once/twice to undo the back door.
If I can remember the lowest wire is black (earth) the top wire is brown/pink and has a battery voltage pulse to lock the door and the orange underneath it pulses battery voltage on both the first and second presses of the plipper to unlock. (No need to test but I think the pink pulses battery voltage just on the first unlock press)

Whilst not 100% assured, basically If you have those values, then get another door lock. You can always hold the replacement lock in your hand and plug the wires in to test before doing the swap. Remember to latch this lock as well whilst testing.