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Discussion Starter · #1 ·
So I have had my toy for a week now, 2000 TD5 in a reasonable condition.
I picked it up from Huddersfield on the 28th drove it back to London no issues and then driven about locally still no issues
I parked it up on Saturday 4th and not touched until this afternoon and there youhave it won't start battery was flat.
Called the AA they jumped started it and stated that battery is good and alternator is good but it appears there is a drain of about 3 Amp when all is off and locked up NOTHING LEFT ON
Now I gota investigate it so before I go sniffing around to the unknown abyss, does any one know of any common known issues ?
This is a UK model 2000 TD5 ES with ACE



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I'd go a little further than the auto club on investigating for problems.

I don't know what batteries are like these days in the UK, but here, if you get three years out of one, you've done well. I replace every one every two. They're cheap insurance. You can get a good charge on it and have it tested, but I've had batteries that tested good but would drain if left for a couple days.

In order to get a good current draw test, you need to put a jumper between the positive terminal of the battery and the battery cable, then connect an ammeter in parallel. Then disconnect the jumper. Let the ECM go to sleep and see if you have draw. I don't know what sleep draw is but it should be under 200milliamps. If not, you'll have to start pulling fuses to find the offending circuit. One place that I've seen more than a few failures is alternator voltage regulators. That would be the first thing I would try disconnecting if you find you have a draw.

I just went through this on another truck- ended up being the intermittent op circuit in the rear wiper. The wiper was stuck and the controller kept pinging the motor. It would give a 5 second spike at 6 amps every 20 seconds or so. Because it was stuck, it never went to the park position so it continued to actuate with the key off.
 

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Discussion Starter · #3 ·
I'd go a little further than the auto club on investigating for problems.

I don't know what batteries are like these days in the UK, but here, if you get three years out of one, you've done well. I replace every one every two. They're cheap insurance. You can get a good charge on it and have it tested, but I've had batteries that tested good but would drain if left for a couple days.

In order to get a good current draw test, you need to put a jumper between the positive terminal of the battery and the battery cable, then connect an ammeter in parallel. Then disconnect the jumper. Let the ECM go to sleep and see if you have draw. I don't know what sleep draw is but it should be under 200milliamps. If not, you'll have to start pulling fuses to find the offending circuit. One place that I've seen more than a few failures is alternator voltage regulators. That would be the first thing I would try disconnecting if you find you have a draw.

I just went through this on another truck- ended up being the intermittent op circuit in the rear wiper. The wiper was stuck and the controller kept pinging the motor. It would give a 5 second spike at 6 amps every 20 seconds or so. Because it was stuck, it never went to the park position so it continued to actuate with the key off.
ct090 I intend to go further but your input does helps, I will have a look In the next few days pull some fuses and see if I can find the culprit circuit.
I do have a fault (leak) with one of the ace hose which await repair, would the controller try to communicate with the ace whilst the car is off ?

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Discussion Starter · #5 ·
I think i found the culprit , there is significant amount of amperage coming out post ign off, it appears that its coming out of the ABS circuit as the issue is eliminated by disconnecting the circuit (engine bay f11 taken out) there are many forums talked about this in the recent few years but no one has actually put a solution up
meanwhile i don't see why a circuit drawing that much current would have to stay live after ign off for that long which in turn draining the battery (btw i now have brand new landrover battery and its fell victim of above as well)

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I don';t believe the ABS controller is VIN-specific, so you may be able to just swap it out. That's the only thing in that system that uses current without going bang. You should be able to pick up a used one for almost free.
 

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The most well-known phantom battery drain cause is the self-leveling suspension. Did your truck once have air springs in the rear and was converted to coils? If the BCU setting wasn't changed from air springs to coils the BCU tries continuously to run the air springs pump, draining the battery. If you're not sure whether or not it once had air springs let us know and we can walk you trough how to find out.
 

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Discussion Starter · #8 ·
The most well-known phantom battery drain cause is the self-leveling suspension. Did your truck once have air springs in the rear and was converted to coils? If the BCU setting wasn't changed from air springs to coils the BCU tries continuously to run the air springs pump, draining the battery. If you're not sure whether or not it once had air springs let us know and we can walk you trough how to find out.
yeah taken the fuse out and intending to do the following fix tomorrow, i may as well do it to the ace circuit and also remove the trailer light circuit as im not using at the moment
and yes i did have a air suspension and looks like previous owner replaced it with springs but don't think a tsb update was done.
my battery is brand new with the correct dealers part number.
have a look at this fix ... (i will post further once i have done this and monitored it for a few days)
https://www.aulro.com/afvb/discovery-2-a/115399-fix-discovery-battery-drain.html

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The most well-known phantom battery drain cause is the self-leveling suspension. Did your truck once have air springs in the rear and was converted to coils? If the BCU setting wasn't changed from air springs to coils the BCU tries continuously to run the air springs pump, draining the battery. If you're not sure whether or not it once had air springs let us know and we can walk you trough how to find out.
First of all it's not about BCU it's about the SLABS and if the battery is drained there's a fault within the system or the battery is weak cos that drain from SLABS is not supposed to last more than 1.5 hours after the ignition was off, that's set from factory as to not reset the counter which protects the compressor from ecxeeding it's duty cycle and 1.5 hours of extra 250mA drain should not flatten a good battery ... considering that the drain is there all the time is a common mistake cos usually when somebody wants to measure it opens the door first to release the bonnet and a door open signal energises the SLABS for 30 minutes also with a reason(it's explained in the system's description) so off course that the extra drain will be there again like it was there all the time while it wasnt... provided there's not some other fault present which keeps the SLABS under power constantly then that fault should be fixed rather than "bypass'' it with a relay...IMO this "mod"(which can be called bodge) would only reset the counter all the time and that can lead to compressor failure due to exceeded duty cycle if a bag is leaking so if you want to keep the SLS in case of a bag leak you might have to buy the bag + spend on fixing or replaceing the compressor....not some brilliant ideea IMO
 
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