Discovery 300tdi electrical issues, I think I'm going crazy!

Afternoon guys, I've been a member on here for a long time, but never posted.

I'm Greg and live near Basingstoke, have had a disco 300tdi for only about 8 months now.

I am having big issues with the electrics as of today, here is what happened.

Stopped driving and went in to shop, I did not lock the car. After about 15 minutes in shop, return to car, I have tried to start it but nothing at all happens. Temp gauge rockets up off the scale, oil and batt light come on, but no glow plug light.

Eventually work out that if the steering wheel in a certain position all dash lights then ignite, and engine will start.

As soon as engine is running all electrics die, no indicators, wipers etc.

I called the AA who came out and scratched his head for a little while, and decided it must be ignition or ignition relay and left me with it.

I'm not sure I trust him, as I have no idea how turning the wheel can make the car start.

There doesn't seem to be in chaffing wires on the steering system anywhere, I have taken steering wheel, indicator / wiper stalks, ignition barrel off and tried and the same thing happens when wheel is turned.

Anyone got any ideas? It's driving me mad!!

Thanks, Greg

I would suspect the ignition barrel but only guessing as it needs a more detailed explanation.
If you've got an immobiliser it could be that at fault as well but as i said it's only guess work.

Ok so a bit more information.

When key is in ignition and turned to 3rd click there is no power to anything at all, steering wheel must carefully be turned to a very precise position. Once in this position everything suddenly seems fine.

This also applies when the key is not in the ignition, (but it is impossible to find said position due to no warning lights on dash.) Car can then be locked with remote fob whilst in this position.

Does anyone know of any link between the steering position and the main power feed? I really cannot see how there can be any link.

have you looked all down the steering column to see if theres any wires tangled up in it anywhere... dont forget the engine bay side aswell.....

Checked all along steering column, also under the bonnet. Certainly can't see any wires anywhere near the column.

Thanks for your suggestions. I've been out for another try this eve with no luck.

Possibly going to have to replace all ignition / immobiliser parts one by one until sorted!

This is an absolute stab in the dark but........
The immobiliser uses a transponder in the ignition barrel which receives a signal from your fob when it is close to it. That is the only thing I can think of which could possibly be affected somehow by moving the wheel but I have absolutely no idea how!

Problem solved!

For future reference guys, CHECK YOUR EARTHS! This very confusing fault was caused by a bad earth fault on the negative battery strap, the electrics must have been earthing through the steering column! :doh:

Cheers for all your help. I hope my stupidity can one day save someone else hours of fault finding.