240 General: Tailgate Central Locking:~

[Bob Meadows]

1988 240 GL Estate: ~
The tailgate central locking motor has stopped working i.e. no movement when the system activated from the driver’s door (locks/unlocks fine with a key) all other electrics through the tailgate wires are working the various parts- all lights- widow wiper etc.
Should I be looking for a break in the loom for the tailgate lock or any other related faults?
I believe the loom runs through the offside hinge for the C/L motor.
Thanks Bob.

[CosmicBike]

Mine doesn't work either, fine on key, but not with central locking. All other tailgate functions operate fine. I know why though, as I can see the cable clearly broken at the hinge. It's on that long to do list..

[Clifford Pope]

It's usually a broken wire, but could be the mechanism in the latch sticking.

[Bob Meadows]

Thanks for the replies:~ thought as much, I will have the postmortem quite soon, Bob.

[Bob Meadows]

Started the investigation as to why the tailgate lock has stopped: ~

The central locking motor within the tailgate has now been removed- initially the two connector’s for the above seemed quite damp- white snap together fittings for a Blue & Yellow wire. Tested the cables to make sure that they had power- you can do this with a 12v test bulb, just push the test wires into the loom and turn the door key to lock/unlock- the bulb will light up if powered proving that no breakages with the loom exist. The polarity is just switched here so no additional earth for the test. I removed the motor to grease the internals etc. and check separately- all fine and in good condition. The problem still exists even though the C/L is working and upon viewing the actuating rods they all pull in the right way etc. The sliding bolt that I suppose connects to the actual handle latch just slides back & forth. At that stage I had to stop progress as it was dam cold and things where in danger of falling off!
I can’t see anything that obvious at present so need to check further- but getting there.
Bob.

[Clifford Pope]

From memory I think the plunger bolt on the end of the activator is switched between two positions. In one it allows operation of the release latch when you try to open the tailgate, but in the other it doesn't engage so the handle just flaps uselessly - ie locked.
I do remember that having first assumed it was the electrical activator not working, in fact all it needed was a squirt of WD40 on the sliding mechanism and some waggling about.

[Bob Meadows]

Thanks Clifford:~ I don't see anything amiss in terms of broken parts/loose inside the tailgate. You may be right regarding the latch as I have noticed it can get stuck as you depress it - I can't quite figure the internal action of these two parts at present (but I will) so the next stage will be to remove the same.
Update later.
Thanks Bob.

[Bob Meadows]

Working Again: ~
It turned out to be a little confusing initially- the tailgate motor worked in the raised position but nothing when closed! The next approach was to look for a broken wire, I did remove the lock mechanism and this has also been cleaned. The older grease is now renewed with copper slip to include the outer door parts. A very small adjusting tab exists if you look at the side of the lock when the tailgate is lifted- this was previously hidden by grease on my car- it will lock the inside pull handle if you wish. The inner lock mechanism is fiddley to remove but does come away with a little twisting. As previously mentioned a sliding bolt allows the press in handle latch to depress or not. A couple of wire rods from the electric motor work this bolt -left/right- access to the rod clips isn’t easy so it is better to complete the linkage prior to putting back in place but leave the more accessible far left clip to last (left side as you sit in the boot etc.)
I found the blue & yellow central locking motor wires to be on the point of breaking just at the flexing point under the hinges- they both snapped upon exposure. I removed the hinge with care by propping up the tailgate with a broom, all a bit awkward as I had to do this alone. Rear part of headlining was pulled away exposing the loom connector, I soldered in four new wires (yellow-blue-grey & black) making the loom longer.
The solder joints have been covered with shrink on sleeves- you can pull enough wire out of the tailgate to enable work to be done above the hinge bolt holes (do not pull all the loom out) the new joints are now hidden inside the door away from the original flexing points.
More sleeving has been added to the new wires and this runs as normal through the underside of the hinge, new solder joints also made to the connector that goes under the headliner and once again all wires have been sleeved- extending the loom does give you more room to renew and adjust the wires.
Additional work carried out is to renew the earth wire strap that runs between the static & opening parts of the hinge, reseal the bolt holes with Dum Dum ( no longer available but you can reuse the existing or use windscreen sealer- waxoyl all hidden hinge parts to include the gaskets.
Once all the above had been completed the central locking for the tailgate works as normal from the driver’s door.
Hope it helps
Bob.