Guys,
the earth strap I fitted was heavy duty starter motor cable, about 4 ft, Purchased from a motor factor and I soldered an eyelet on each end. I then secured one end under the little 6mm thread sticking up of the battery terminal on the negative side & secured the other end under a gearbox securing bolt right by the starter motor.

To solder the cable did require using a small blow torch to get the heat into the eyelet to make the solder flow and good flux was needed as well. Mind your fingers, it gets hot & I did these away from the car ( H&S) LOL

This was originally fitted to fix "HDC disabled" appearing on every start up , but it also had the effect for me of transforming the gearbox change ( mines an auto) and a vast improvement in MPG, from 23-26 best to 33-37 and often 40+ on a long run !

Some Freelander are fitted with Pyrotechnic cables to the battery, these are designed to separate the cable from the battery in the event of a big accident to reduce the possibility of fire.
My earth strap doesn't have one of these fitted but my + battery cable does.

After my experience of improved MPG I did some research to find that there is a company selling ultra earth cables who claim anything up to 22% improvement in MPG with reducing electrical noise causing confusing signals ! Who knows whether its hype but for me it worked anyway.

There was a time long ago when fitting two gearbox to chassis earth straps was the norm.

The mean bean counters put an end to it  Another member of the failed FL2 clutch/DMF club, twice.

There's no doubt that there can be truth in this, the question is, does YOUR car need it?
If any of your cabling, be it positive or negative have high resistance joints then the voltage will suffer and could result in sensors misbehaving.
It would be good practice after a while to check tightness and clean all main earthing cables, main power cables and battery posts to keep them to minimal resistance.
Again if gasket material, threadlock on bolts etc is used between engine and gearbox then the gearbox will have to find another earth return path unless it has a dedicated earth wire. So there is no harm done in additional earth wires.

The thing is, don't add additional straps and forget to check/clean what you already have.

Last edited by EYorkshire on 29th Nov 2011 3:12 pm. Edited 1 time in total

We used to specify two earths because of the harsh enviroment and safety.
If you've only one and it fails, the engine stops or even worse. Another member of the failed FL2 clutch/DMF club, twice.

Well pegleg,
if you study the root of the earths on a freelander I feel its a very poor design. One cable from battery earth to body up by bulkhead.
The 2nd earth is from the body n/s almost by the chassis leg to the gearbox ! Now years ago at least the earth cables would be twin off the battery, with one eyelet to the body & the other too the gearbox / engine

When that starter cranks on a cold morning there is a huge current draw relying on multiple connections here & there !

I actually put an anolouge voltmeter from the battery post ( earth side) to the engine block and when I cranked the engine at -6 degrees ambient temp I had 3.5 volts at cranking !!!!!!!!!! indicating a really poor earth, this in turn caused the battery voltage to drop to 7volts @ cranking causing loads of fault codes in many modules .

If you add the 3.5 volts to the 7 it makes 10.5 volts which is roughly what you would expect at cranking with a perfect earth. So in essance its easy to see if an earth is working, use an analouge volt meter across any earth point to test it and under load it should never exceed 0.03 of a volt !

Its just so frustrating that a dealer just couldn't carry out one of the most fundamental tests which may of resolved all the issue's mine suffered from new.
I believe that the HDC issue is a common one that has now been fixed with an update, and all that does is to increase the voltage variance allowed by a module before it flags a fault ! this doesn't fix the fact that the battery voltage is dropping excessively ! most likely due to poor earth issue's !

It would be very interesting to see if anyone else takes the trouble to use a voltmeter or scope to capture voltage drop at the battery during cranking and any voltage demand across any earth points on starting up in cold weather. You do need a fast scope & quality volt meter and a second person to hit the starter button whilst watching the reading

Thanks for the replies guys very interesting, will have to get on to it in the very near future. Gone, 2007 TD4 SE Auto Baltic blue, clear side repeaters, full sized alloy spare.

English by birth..... Yorkshire by the grace of God.

Oldgeezer,
Agree with you about earth cabling. Most vehicles are like that today i'm afraid. We also measured the resistance of the circuit during cranking which had to be within certain limits.
We also used a Fluke ScopeMeter which has a trigger facility so you didn't need two people to 'catch' the waveform.
7v shouldn't normally be a problem to the modules; they should be okay down to around 5v Another member of the failed FL2 clutch/DMF club, twice.

Pegleg wrote:

7v shouldn't normally be a problem to the modules; they should be okay down to around 5v

well my FL2 would produce 8-10 faults codes in a week, mostly caused at starts & all related to voltage too low & voltage too high ! clearly related to sudden voltage surges ! & always on start up ! Quite possible the voltage used to drop well below 7 volts, my measurement was only one cold morning with a battery that had been on charge all night ! It was the only way it would start ! Normal according to a dealer ! utter carp. Never had to put it on charge since !
On start up my wipers would always trigger ! except when in a dealer of course ! except the day i collected it as soon as I hit the start button the wipers did their normal once sweep ! windows had a mind of their own as did the lights ! I also had 4 dash panels , all damaged due to voltage spikes ! along with many other modules.
All settled now since extra earth & one of the original earths was replaced due to internal corrosion, possibley caused by a chemical reaction when the cable was originally assembled & shrink wrapped ! trapping the corrosion.
Most modules are designed to run at lower voltage but depends on what voltage level they are set to trigger of a fault code at ! & again depends on just how much punishment they do take.
Don't forget for 3 years mine couldn't even turn over when cold ! it would part crank and stop then turn a bit more and stop just like a flat battery, but of course the dealer could never find anything wrong !!!! It didn't matter how I explained it or wrote it down I think they interpreted it as me having to wait for the glow plugs ! although I made it very clear I was aware of the delay !
My land-rover experience has been an horrendous one and L/rover customer service did nothing to improve the situation until I wrote to the MD.
Just thinking about it now makes me very angry & i'm extremely tolerant ! Rant over

Oldgeezer,
You really have had a hard time of it. I've also seen high resistance on starter circuits when the cable crimp is not soldered. The combination of heating and cooling causes the crimp to relax let alone capillary action of water.
Shame it took so long to sort it, as we both know in the good old days with two earth leads this might have never raised it's head.
I'd hate to think the concequences should the the lead have failed altogether. Another member of the failed FL2 clutch/DMF club, twice.