Afternoon guys and gals, I have an issue with my 07 HSE, for a few weeks now the battery light has come on and off randomly as and when it feels like it. Nothing in particular causes it to come on and I can't fathom out what is causing it, the car still drives fine when the light is on. I have scoured the net and the things that have been suggested I have had a look at, the blue linbus wire that comes from the alternator seems to be a common fault on them, chafing and rubbing through, this all appears to be ok on mine. When the engine is off the battery is showing 12.7 volts on my meter, with the engine running it goes up to 13.7 and if I load it up by switching both electric seats on, the lights and the de-mister it takes the battery voltage down to 13.2 volts. Does this seem a little low?? I was wondering if the alternator was getting a little tired, the car has done 106k miles and the battery is about 5 months old.

It had a spell earlier on this week where it seemed to be on all the time, then yesterday it never came on all day. . . .??? The car is used mainly for short journeys to and from my other half's place of work, but we went away towing our caravan the other week and did a 160 mile journey with it and it came on as and when it felt like it the whole journey. . . . . it's driving me mad. I would appreciate any help on this one if anyone can shed any light on it.

Kind regards Neil.

Search for "earth strap" which may cause your symptoms
I would also have the alternator and battery (I know its only 5 months old) professionally tested
Good Luck No Longer the owner of a 2013MY Fuji White GS

"Fiat Lux" a philosophy not a car

you need to check if its charging when the lights on,its possible that it might be and its just the warning light circuit ,but I suspect not,i think you need a new alternator,just out of interest whats the mileage?its unusual for these to fail in my experience,at low mileage.

Hello there,
Sorry for the slow replies. I've spent a bit of time messing about with it. The light hasn't been on for the last few days now, but last weekend it was barely off. The battery appears to be charging with the light on according to my meter. I have also had a good look round the earth lead that mounts to the car body, that appears to be all in very good order. when the battery light was on the other night whilst I was messing about with it, I put a jump lead from the earth post to the main engine casing to see if a poor earth was the cause and that didn't make any difference either. The mileage on the motor is 108k. it is driving me mad now. I can't get my head round the 'randomness' of it. . . .?????

I think westville was referring to the "extra" Earth strap which seems to cure a multitude of errors.

You could get one of these:

Click image to enlarge

Hi! I had exactly the same issue. Was put down to a faulty alternator by the garage. After paying £300 for a new unit and a further £130 having it fitted it turned out to be a chaffed earthing wire from the alternator which runs back to the wiring loom.

I had a secondary earthing strap fitted at the same time which should solve a number of problems and errors we have had in the past. 2007 LR Freelander 2 GS - factory tints, LR mud flaps, 2013 facelift)
Problems/solutions include: rear diff pinion replaced, stearing rack and pump replaced, alternator earth cable replaced (plus new alternator as misdiagnosed), throttle body replaced, MAP sensor replaced, secondary earth cable...
2002 MG TF 160 1.8i VVC - Gone
1998 MGF 1.8i VVC - Gone

Hi everyone

Been reading your thread and thought that I would share my experience, especially as I fixed it today.

I am an electronics engineer by trade and like a challenge, which I certainly got with my 2007 Freelander TD4 XS.

This fault has been described as a chaffing fault, but my own experience was different.

Indeed the blue wire from the top of the alternator was broken, and this sends messages to the cars computer from the alternator.

BUT it appeared to be intact on inspection, which is relevant to this thread, as it could fool you into thinking it is o.k. when in fact it is not. It was only when I gave it a gentle tug that it came away from the loom, at the very point it exits the loom.

On closer inspection the copper inner of the blue signal wire has corroded inside the plastic insulation. I pulled the insulation away and green powder came out for about 3mm before I found copper. Very bizarre, but I suspect that the insulation over time hardened and cracked where it exits the loom, allowing water etc in, and capillary action and water did the rest.

To be honest I am a little disappointed at the poor quality of the wire used in the loom. In my opinion it should have been arctic grade plastic insulation, which stays flexible at low temperatures, and tolerates heat well too, but I guess the accountants wouldn't allow that expense, even though this was not a cheap vehicle when new.

Another fault that this broken wire threw up was the engine hunting on tickover if you revved the engine and took your foot off again whilst the heater is on auto. Even more strange is that the engine stops hunting if you switch to econ mode on the heating.

Electronics in cars eh,......

Another top tip as they say is: always disconnect the negative battery terminal BEFORE you do any work under the bonnet, and always connect back up AFTER the last job, so that the onboard computer doesn't see any abnormalities when it powers back up.

Happy Freelandering

Refurb Pete

p.s I dread to think how many alternators and batteries have been replaced by "experts" because of this wire, so I hope this info helps.

Great forum by the way

P.s. just a little more info as I have been asked about this post. In order to get to the wire you will have to remove the fuel filter and cover plate, and if you keep the filter upright there should be no need to bleed the system when you put it back. Then if you need more room, remove the fuel filter mounting. It is held on by 4 bolts. Incidentally the oil cooler pipe is directly below where the wire exits the loom, so would support my heating up, cooling down, insulation failure. When I re joined the wire I used glass fibre cable heat shield tubing for additional protection.

Apologies for the thread resurrection! The battery light has been lit on my wife's 2007 i6 for a couple of month now. I stuck a meter across the battery and saw 14ish volts when running so I put it down to the infamous blue wire issue and added it to the list of jobs.
Well today the electrics died resulting in us being stranded until recovery arrived.
I understand that the blue wire carries the signal to tell the ECU that the battery is receiving a charge but does it also tell the ECU that the battery 'needs' a charge. ie, are my flat battery woes still related to the blue wire vs a duff battery or duff alternator?
Thanks in advance gurus!