Electrical fault?
Author
Discussion

-DrEw-

Original Poster:

25 posts

220 months

Saturday 27th October 2007
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Hey as some of you may know weve got a 1996 2.5 dt which basically is a heap of sh*t lol,

Anyway every since we got it we've had this problem and have tryed almost everything

The battery just keeps going flat, we've had 2 new alternators and 3 new batterys, they work fine for about 1 month then they just start going flat, we have to keep a booster pack with us and use it almost everytime we need to start it.

weve had it connected to the diognostic computer and no problems show up, and we've had a resistor chip fitted to the plug (apparently this is meant to solve it) weve even had to switch the interior lights off.

Anybody got any ideas?

Ordinary Bloke

4,559 posts

219 months

Saturday 27th October 2007
quotequote all
Draw a diagram of the fuse box, which values in which places etc, then pull them all out.

Get an ammeter which can show a reasonable number of amps, perhaps 20A. Put it between the battery +ve terminal and the red lead to the car. You should see 0 Amps.

If not, you have a current leakage before the fuse box. Try unplugging the alternator or anything that doesn't go through the fuse box.

Now start putting fuses in. The only 2 things which normally take power in a car when switched off are the clock and the alarm (if fitted). When you add a fuse, you'll suddenly get a reading on the ammeter.

A battery has 10's of amp-hours so it'll be a big value, perhaps heated rear window or something (do Landrovers have such luxuries?). If it's a 60 A/H battery and the ammeter's saying 60mA (0.06A) then it would take 1000 hours to flatten the battery.

If you get all the fuses in, and still a low reading on the ammeter, call an exorcist, or look for squirrels with jump-leads.


-DrEw-

Original Poster:

25 posts

220 months

Sunday 28th October 2007
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Tryed it all already lol, i know the cars computer can flatten the battery if its left open, but ours is left locked with everything switched off

Ordinary Bloke

4,559 posts

219 months

Sunday 28th October 2007
quotequote all
My point is, looking at the ammeter you can see the current being drawn. If it's 1 Amp, then a 60A/H battery should last 60 hours etc etc.

I can't think of any reason why a car should take more than 0.1A.

So unplug stuff until the problem goes away.

If it's not taking more than 0.1A, look for current-thieving squirrels etc.

GKP

15,099 posts

262 months

Sunday 28th October 2007
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It sounds like your BECM isn't going to sleep properly. It might be worth checking the door switches (especially the drivers door and tailgate) to make sure the switchs aren't leaving the BECM on.