tonywalsh

Thanks yet again Jason. If you see my other post you'll see that the problem you outline here was the root cause of two issues. Thanks to you and one or two others I found 3 wires broken, fixed them and all is now well.

Absolutely spot on kfk! 3 broken wires inside the flexi boot at top of tailgate. Did try pulling them the other day but didn't reveal the problem. Stripped it down and hey ho. All absolutely 100% now. Most grateful for all the suggestions and help.

Absolutely true. I'll attack it tomorrow and keep you posted. Many thanks.

Wise and perfectly sensible words kfk! I will of course do that tomorrow. It doesn't explain the behaviour of the wiper though. I must admit I can live with that fault but the tailgate failure is a real problem since I work out of the vehicle and open the tail umpteen times a day, that alone could bolster your theory of wiring problems! Many thanks for now and I'll update when I find something.

Ok many thanks so far. Forgive but I was trying to shortcut through a fairly long sequence of faults. But here goes! Some weeks ago the rear windscreen wiper began to exhibit a fault. It swept 3 times when the central locking plipper was operated when opening the car. It repeats that fault after a short (maybe 3 or 4 mins) delay when any door is opened. It also does not park, simply coming to rest wherever it stops. The intermittent wipe also does not work and the same 3 wipe sequence happens when you operate from the stalk. 2 days ago the tailgate lock refuses to open either from the gate handle or from the interior button, the only recourse is to use the screwdriver in the hole trick to open the gate. All other doors work ok with the key fob or from the interior locking button. Yesterday I had a diagnostic from an indy auto electrician who tells me that the fault is with the Body Control Unit (BSI) but this can only be fixed by the main dealer since it is coded. On investigation I found a BSI reset sequence which it seems would be worth a try. Done that but no improvement. I've also discovered that I can get a reman unit for £125 on line by sending my old unit to them which is then returned, refreshed and avoiding re-coding and what I understand would be a bill many hundreds more. I'm not an auto engineer, but I am an engineer and electrician so naturally I am happy to have a go. But I will be guided by all of you who are more expert than I am!

Mmm. Bit of a mystery now! Assuming I'm looking at the correct unit which is the one to the left of the fuse box under the bonnet, it bears no resemblance to the picture posted on BBA reman site. Is there more than one type of Body Control Unit? My car is a 51 plate C5 Hdi 110 estate. The BBA picture has all manner of muti plugs on the top of it. The unit I'm looking at is a metal bodied box with three (I think) multi plugs at the rear.

Sorry, it's the Body Control Unit I need, but thanks Randombloke, most helpful.

Can anyone tell me where this unit is located on a 51 plate C5 Hdi (110)?

Thanks Jason, I'll check that out in the morn. Assuming it's not absolutely pouring with rain!

Thanks but as I said the mechanism itself works fine. The fault is elsewhere.

Hi all, '51 plate C5 estate tailgate lock won't unlock. All the other doors work. The tailgate remains firmly locked whether from the key fob, gate handle or internal button presses. The only way to release it is with the screwdriver in the hole trick. I've removed and tested the lock unit and it is fine, both the motor and the microswitch are ok. Removed every fuse and they're ok too. Must be missing something! Any ideas would ease the headache and the pain of having to climb over the rear seats everytime I need to open the tail! Is there a relay or something else I should be looking for?