Hi,

Bought a 2006 X5 second hand. Went to fit the tow bar (BMW part number 6761678) and a) it does not lock open on turning and pulling out the knob, ans b) it locates into the groove but the knob does not register as locked...nor can you use the locking key.

try as I may I cannot get it out in this position without again turning the knob, I feel it too much of a risk to start towing my Shetland without confirmation that the system is totally secure. Has anyone met this problem before......and does anyone on where a fully working u it might be that is for sale. Begrudge paying BMW prices when it could be that even that one does not work.

splodge

Hi Roger...welcome to the Forum!
Sounds like it needs some WD40 as something maybe sticking? When it locates and you turn it surely it should snap into place...if not then the mechanism maybe sticking slightly. Not sure if I'd want to use to tow with if I'm not satisfied that its not secure.  Check eBay for replacement ones, there are some on there but they're not cheap!

Anyone else know what the issue is and a solution?

This one does not turn and click. You pull out the knob on the side and turn it and it should lock the three locking balls into the housing. You then push it vertically into position at which point the knob should Spring free and return to its original position.

i have flooded it with WD40, I have carefully removed the rust starting on the locking balls but it still will not lock off in the unlocked position. When you get it into position the two "V"s on the towbar engage with the inverted "V"s in the housing and are snug and tight. The towbar will not come out....BUT the knob does not return fully, does not snap back to the body of the unit and will not allow the locking key to turn

That does not sound like a good situation then as you say it fits well but if it does not fully lock in then it's probably not worth taking the chance.