Discomadness wrote:

Hiya buddy. The search continues. Gear box oil level ok.
Plugs at the rear checked and ok. Bit of a chafe against the strut tower for the wiring but nothing rubbed through.
Disconnected the radio capacitor. No difference.
Going to remove the switch surrounds for the hdc switches etc and check I didn’t yank the wiring with the epb cable.
Checked the wiring around the battery all ok.

Dad picking up a new 100ah agm battery for me so I can eliminate that, it had dropped to 12.3v over night.
Thanks for digging the info too mate.

  

PROFSR G wrote:

gstuart wrote:

PROFSR G wrote:

I've not come across Diesel deteriorating in that short a period, I think in the end the answer is going to be something small. Right now the best I can offer you is to keep your approach simple, if the car was fine before work began its likely that something did not go back quite right. Think about everything you did working backwards. If you need anything and its late you can pm me, I'll be burning the midnight oil in the garage too

Hi mate

Indeed agree with u how it’s just pinning it down to something simple , where so many systems talk to one another and just got to have that one connector etc to cause the issues

Know when I virtually had my interior apart looking for an airbag fault and unfortunately took time going through everything, great feeling through when through help from the forum and pat at gap got it resolved

Where connectors come apart just think it could be just a few bad pins with some dirt etc that may be causing this ????

Hi gs

I think you're bang on! and here's the reason why which I've only spotted now.

Discomadness wrote:

The car was running ok before. I’d have a occasional transmission fault when reversing and then shifting into drive but not all the time.

I think this prior intermittent issue which may have been a faulty connector / weak cable has now possibly deteriorated completely whilst pulling the various plugs apart. A precise and scrupulous inspection of each cable on all connectors might now be the only way forward. With absolutely nothing else to go on, this is a smoking gun for me!

  

Discomadness wrote:

Oh dear god. Where do I start with that !

I’m getting out of my depth with electrical fault finding now.

I checked the wiring under the centre console. All ok. The epb release can only really go straight up or down, it was actually sat in its little clip recess too.

I’m starting to think your right though perhaps I have got a wiring fault somewhere. Does anyone have any common areas where failures occur ?

The one thing for me is that the F is there as soon as ignition goes live, it’s not even had to think about it. So something is off.

  

gstuart wrote:

Discomadness wrote:

Hiya buddy. The search continues. Gear box oil level ok.
Plugs at the rear checked and ok. Bit of a chafe against the strut tower for the wiring but nothing rubbed through.
Disconnected the radio capacitor. No difference.
Going to remove the switch surrounds for the hdc switches etc and check I didn’t yank the wiring with the epb cable.
Checked the wiring around the battery all ok.

Dad picking up a new 100ah agm battery for me so I can eliminate that, it had dropped to 12.3v over night.
Thanks for digging the info too mate.

Great that checked out

Hope u don’t mind me saying ur not fitting an AGM battery to urs are u , think the alternators produce to high voltage for them,

No probs ref the info, this F and occasionally going into reverse is a red flag , been looking for a good few hours but nothing yet , see the F is limp mode and it’s way of protecting itself

Good call as u say ref the wire , never know if it was accidentally pulled by mistake

Plse let us know how things are going

Hiya mate

Err didn’t know that ref the agm battery I rang supac who are near me and that’s what the recommended for the car because of the load... crap I better ring him and cancel that !

This oil leak around the mecharonic sleeve is bugging me also. Perhaps that’s getting oil in the loom maybe ? I don’t know. I’m clutching straws now.

gstuart wrote:

Discomadness wrote:

Oh dear god. Where do I start with that !

I’m getting out of my depth with electrical fault finding now.

I checked the wiring under the centre console. All ok. The epb release can only really go straight up or down, it was actually sat in its little clip recess too.

I’m starting to think your right though perhaps I have got a wiring fault somewhere. Does anyone have any common areas where failures occur ?

The one thing for me is that the F is there as soon as ignition goes live, it’s not even had to think about it. So something is off.

Just found the fault test sheet for the gearbox , has in there which pins to check with a multimeter

http://media.disco3.co.uk/gallery/albums/u...Manual.pdf

Discomadness wrote:

gstuart wrote:

Discomadness wrote:

Hiya buddy. The search continues. Gear box oil level ok.
Plugs at the rear checked and ok. Bit of a chafe against the strut tower for the wiring but nothing rubbed through.
Disconnected the radio capacitor. No difference.
Going to remove the switch surrounds for the hdc switches etc and check I didn’t yank the wiring with the epb cable.
Checked the wiring around the battery all ok.

Dad picking up a new 100ah agm battery for me so I can eliminate that, it had dropped to 12.3v over night.
Thanks for digging the info too mate.

Great that checked out

Hope u don’t mind me saying ur not fitting an AGM battery to urs are u , think the alternators produce to high voltage for them,

No probs ref the info, this F and occasionally going into reverse is a red flag , been looking for a good few hours but nothing yet , see the F is limp mode and it’s way of protecting itself

Good call as u say ref the wire , never know if it was accidentally pulled by mistake

Plse let us know how things are going

Hiya mate

Err didn’t know that ref the agm battery I rang supac who are near me and that’s what the recommended for the car because of the load... crap I better ring him and cancel that !

This oil leak around the mecharonic sleeve is bugging me also. Perhaps that’s getting oil in the loom maybe ? I don’t know. I’m clutching straws now.

Think the agm batteries are for the later D4s only , hope I’ve got my facts right

That would also worry me with the oil leaking , have put a few links and shows u how to replace the sleeve etc , know it’s not a 5 x min job but at least the job will be done and dusted for u and not have to worry about it in the middle of winter

If u can’t find it have stored them just in case, alas may or maybe not cure the issue but would worry me with it leaking

  

Discomadness wrote:

gstuart wrote:

Discomadness wrote:

Oh dear god. Where do I start with that !

I’m getting out of my depth with electrical fault finding now.

I checked the wiring under the centre console. All ok. The epb release can only really go straight up or down, it was actually sat in its little clip recess too.

I’m starting to think your right though perhaps I have got a wiring fault somewhere. Does anyone have any common areas where failures occur ?

The one thing for me is that the F is there as soon as ignition goes live, it’s not even had to think about it. So something is off.

Just found the fault test sheet for the gearbox , has in there which pins to check with a multimeter

http://media.disco3.co.uk/gallery/albums/u...Manual.pdf

Gear selector position has got me interested... I know that’s been disconnected and the pivot on the box was moved about.... how can I tell if it’s in the right place ?

  

Discomadness wrote:

Oh dear god. Where do I start with that !

I’m getting out of my depth with electrical fault finding now.

I checked the wiring under the centre console. All ok. The epb release can only really go straight up or down, it was actually sat in its little clip recess too.

I’m starting to think your right though perhaps I have got a wiring fault somewhere. Does anyone have any common areas where failures occur ?

The one thing for me is that the F is there as soon as ignition goes live, it’s not even had to think about it. So something is off.

You don't need to be put off by the prospect of an electrical fault. In most cases these can often be traced with a little imagination. There are of course the exceptions, but we'll come to that when the need arises.

The mechatronic terminal at the g/box might yield something, ditto for the transfer case motor and anything else you touched to get the body off. The shortest way might be to sit in the car Ign on, and have someone under the car move the cables at each plug in turn. If you hear a bong or the dreaded "F" off, then you will be on to something. Take your time, be methodical and probe everything!

Its better to try this first rather than another wild goose chase. Keep a sharp eye on the dash as the cables at each plug are probed, and probe along the length of the cables where they arrive at each plug.

I say again, take your time and have a competent assistant who understands what you're looking for!
See how that goes and come back