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OK folks I'm a bit stumped I've got 2000 2.5td p38
enter image description here
get this going to alternator enter image description here
and this is amperage to the starter all while ticking over BeCM is sleeping when turned off
admittedly I've got a leak on fuel injection pump that is letting air creep in the system when left standing
when I go to turn it over she big sluggish starting if leave the truck standing for few days and go to start it more like I've got flat battery if put jump leads on it fires up better
would anyone have a idea it would be

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Check leads to starter --- could be relay issue

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earth on starter does look a bit rusty will have look and clean of it tomorrow

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Is that the current going to the starter at idle? Major issue! However, if it is -30A as the meter tends to indicate, is it in fact the charge current going back into the battery? I don’t know about the diesel, but the V8 has a wire from the alternator to the starter, using the starter cable to link the alternator to the battery (why? Oh for god’s sake why?) on some of the early vehicles. Later ones seem to have been modified to take the alternator output directly to the battery.

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Marshall8hp wrote:

Is that the current going to the starter at idle? Major issue! However, if it is -30A as the meter tends to indicate, is it in fact the charge current going back into the battery? I don’t know about the diesel, but the V8 has a wire from the alternator to the starter, using the starter cable to link the alternator to the battery (why? Oh for god’s sake why?) on some of the early vehicles. Later ones seem to have been modified to take the alternator output directly to the battery.

sorry your right thats what coming from alternator I've got good voltage going to and from where it should be it just if I leave it for a day or two the battery don't seems to have a lot of guts in it and just needs a bit of a boost to get her going it been tested and showing it a good battery

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Check the battery voltage while the glow plugs are on and when cranking on the starter. That will tell you if the battery voltage is dropping too low when under load. Also clean the connections under the bolt of the battery terminal. I had a problem once where that connection was bad and by putting the clamp from jump leads on pressed against that connection so making it good.

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@karlos01 have a look at this chart.

Standard fuse chart

What you need to do, with everything off, and the BeCM asleep, is get your digital volt meter and probe the back of each fuse, where the metal tabs are bare on the back of the fuse. Set the DVM to milivolts and measure the voltage drop. The chat gives you the current being drawn for a given voltage drop and a given fuse rating. In this way you can quickly go over both fuse boxes and see where the current drain is.

GilbertD will be able to confirm, but the only drains you should see, and those minimal, are for the BeCM and the radio permanent live, and (maybe) for the key unlock receiver (for want of a better term).

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Marshall8hp wrote:

@karlos01 have a look at this chart.

Standard fuse chart

What you need to do, with everything off, and the BeCM asleep, is get your digital volt meter and probe the back of each fuse, where the metal tabs are bare on the back of the fuse. Set the DVM to milivolts and measure the voltage drop. The chat gives you the current being drawn for a given voltage drop and a given fuse rating. In this way you can quickly go over both fuse boxes and see where the current drain is.

GilbertD will be able to confirm, but the only drains you should see, and those minimal, are for the BeCM and the radio permanent live, and (maybe) for the key unlock receiver (for want of a better term).

thanks @Marshall8hp
I will get my mate who a auto electrician to go over it with me now we got a chart to work with
be a job when it not cold or raining
again thanks for your reply and help will keep you posted as to what we find

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Might be as simple as battery now beyond its life 🤔 rather than anything else

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batteryis less than a year old on it it a 644 hankook
enter image description here
like the one circled neighbour has same on his and no problems he got it for me same place he got his

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I've got the MF31-1000 on my car and an MF31-750 on the Ascot, you can't get a better battery for a P38, so unlikely to be that.

Once the BeCM goes to sleep you should be looking at a current drain of no more than 20mA which would take well over 3 months to flatten a good battery. Using a high current clamp on meter isn't going to tell you anything, you need something that can measure much smaller current drain.

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Self levelling suspension, have you swapped relays to a 4 pin,,, although it’s going to sleep, are you sure nothing is waking the becm up ?

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750cca sounds a tad low for the diesel unit, i'd be more inclined towards the MF-31 1000 for the diesel.

I have the 1000 in mine and she spins over like a top even after 4 weeks of sitting.

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Might be marginal but it's still far better than a Halfords or similar generic battery. I wouldn't think the self levelling EAS would drain the battery that quickly, it only wakes up every 6 hours or so. My Ascot, with the same battery, was left for over 6 weeks and still fired up first turn.

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On the V8 yes but the diesel is harder to turn over, you've also got to account for the current draw from the glow plugs, which is a fair chunk.

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@karlos01 See Video

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thanks @Marshall8hp I'll have a look at it tonight or when on break

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thanks @Marshall8hp I'll have a look at it tonight or when on break
StrangeRover wrote:

750cca sounds a tad low for the diesel unit, i'd be more inclined towards the MF-31 1000 for the diesel.

I have the 1000 in mine and she spins over like a top even after 4 weeks

battery I got on is exactly the same as my neighbour has on his diesel and he has no problem starting his 3ven when cod like this
did notice yesterday when went to start it thatthr starter has got a flat spot

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StrangeRover wrote:

On the V8 yes but the diesel is harder to turn over, you've also got to account for the current draw from the glow plugs, which is a fair chunk.

Yes but don't forget that the glow plugs won't be affected by the CCA (Cranking Current Amps) figure, as they draw a lot but no more than 100A so would be affected by the Ah (Amp Hour) figure. So leaving the glow plugs powered for an hour would flatten a 100Ah battery but they aren't on for an hour. The CCA figure shows the maximum current it can supply for a short period which is dictated by the internal resistance of the battery. Land Rover specify a 664 battery for the diesel but that number relates to the AH figure and dimensions. A 664 should be rated at 110Ah, which it is, but the CCA from a 664 from different manufacturers varies between 680 and 750A with a 664SHD (Super Heavy Duty) being rated at 870A. So an MF31-750 is an exact match to what LR specify.

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Once I've got the leak sorted out on my fuel injection pump I think I might of cracked it tested my start up to next doors my start up dropped to 8v on first turn over we both think because I'm getting air in the fuel line from pump when I start up it pushing or self bleeding the air out on start up and taking a lot of juice from battery