Defender 90 Earth Straps - Where are they???

Hi,

Ive got a bad earth on my defender 90 (Im fairly sure its an earth issue after reading other threads - eratic temperature gauge, dim headlights, flikering indicators, stereo cutting out when lights or indicators are switched on etc etc). My problem is where to start looking for the culprit!

So far ive checked the resistance between battery end of -ve lead and the earthing 17mm bolt on the gearbox/engine = 0.3ohm - is this close enough to 0.0ohm or should it be exactly 0.0ohm's? ive also checked other earth resistance's like stereo to earth lead (0.3ohms), interior light earth lead (0.3ohms) and earth point in engine bay on bulkhead (3 or 4 earths on 1 bolt) to engine - 0.3ohms?

Is there another main earth strap somewhere - Chassis to Engine perhaps?? Where "should" it be?

Indeed, do you think i'm on the right track or could something else be causing the problem?

Thanks Jon

Reply to
Jon K
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Sorry, can't help there

What reading do you get when you join the meter leads together, my guess would be around 0.2 if so then your reading of 0.3 should be fine.

Try checking the supply too, not just the earth.

Reply to
Simon Barr

Simon Barr wrote in news:bf5r63$bai27$1@ID-

113705.news.uni-berlin.de:

I am the original poster!

My problem was traced to a bad starter motor, then individual wiring problems.

Let's face it, LRs are used off road and the underside is exposed to all sorts of rubbish which retains dampness leading to corrosion and bad contacts.

From what I can gather, my Defender 90 was sitting idle for a matter of years before bought by the previous owner, then sold a few months later at a loss! Some of the electrical problems I had have now disappeared which I suspect was because of poor contact at connectors. Just running the vehicle probably helped solve some of these.

The wiring of a LR is not very complicated and your best course might be to trace individual circuits and connectors. Just get a length of insulated wire and by pass whole sections. If that works, you have a break in the intermediate circuitry!

Derry

Reply to
Derry Argue

Gearbox !

Reply to
AndWhyNot

You need an earth strap from battery to chassis and also from engine to chassis. It doesn't matter where they are as long as they are good thick cables well connected at each end.

Trying to measure earth strap resistance with a multimeter isn't going to show up bad connections. Much better to measure the voltage drop when a high current is passing, e.g. turn everything possible on and measure the volts between the battery post and a clean bit of chassis. Should be 0 volts, certainly not more than 0.2 or so.

Similarly get someone to check the engine to chassis connection while cranking the engine.

Gordon

Reply to
Gordon

OK, thanks. I'll give that a go this weekend.

Where should the engine - chassis strap be and is it a sizable cable / braid like the one from the battery to the transfer box?

the only reason i ask is that ive had a good look arounf the engine bay from above and below and cant see one! The only place i can see an earth point is on the bulkhead more or less behind the dashboard console to the right of the brake servo, this point has about 4 or 5 small wires connected to 1 bolt and certainly dopesnt look "big" enough for a main earth strap.

Thanks again. Jon

Reply to
Jon K

On or around Fri, 18 Jul 2003 11:15:50 +0100, Jon K enlightened us thusly:

gearbox, as someone else said. off the bellhousing, I think, or at the back of the box, onto the chassis. maybe both.

Reply to
Austin Shackles

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