Could it be water damage from its previous ownership it if it's been doing it since you got it?
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Very clear parasitic drain
- Thread starter Chris
- Start date
Well look anything is possible but I have had a lot of cruisers and had some electrical issues. But when it's water (like a leaking windscreen) you get other indications. I've had alarms going off at midnight. Headlights coming on when the vehicle was parked you know? This 80 is simply brilliant. It goes like a tornado, starts on the touch (well you take my point) all the dash lights work, headlights are excellent, charge is good, even the light in the ashtray works. There are no gremlins at all. Now, the one thing that does make me wonder is the additional wiring that was put in for a big stereo. Seems a member of UB40 owned it once and there was lots of silly big speakers in there and an amp. I have pulled nearly all of that out but there may just be something somewhere I suppose. There was a big fuse block for this and I just pulled all the fuses out.
I'll keep going till I find it but in the meantime I am leaving the truck on charge all the time so as not to damage the batteries by flattening them.
I'll keep going till I find it but in the meantime I am leaving the truck on charge all the time so as not to damage the batteries by flattening them.
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- Feb 2, 2013
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- 16,248
Yes but you can leave the lights on with the ignition off so it wouldn't take much to make it a permanent live . I had a short in my 90 and cured it by replacing the indicator stalk .
Can't say specifically Stu. I have to take the dash out soon to put a basic player in and as we know the older dash is a twat to take out without breaking. Once in there I can do the final pruning back to the OEM harness.
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Yes Steve, they do. But pretty much everything goes through those. Whilst the batteries are in parallel, all of the systems actually get pulled from the +ve on the aux battery via a couple of main fuses. Take those out and nothing at all works.
There are two or three fusible links from the RHS battery (on the air cleaner side). I'm pretty sure one is alternator, the other two, possibly the two fuse boxes? I've not gone that far into the electrics (and it is of course possible that mine are different being an 81). I do have electrical diagrams if needed, though I'm not back until tomorrow evening.
I have the diagrams myself but they don't help. The drain has to come from the battery terminal. Whether it goes through a fuse or not isn't any closer to finding the source.I have BOTH batteries disconnected and if I place the ammeter across EITHER clamp and battery I can see the drain. It' not through the alternator as I have completely disconnected that. So this is a drain to earth somehow from some component or cable regardelss of how you supply power to it. What I have not done is break the connection between the two battery clamps (NS to OS charging cable). I could to that and then see if I lose the drain from the PS battery. I might. But that tells me what? Not much. If I lose it from the DS but not the PS then that might point to the change over or some starting component?
Like I say, split it down and watch to see when the drain drops off. By a process of elimination it should be possible with the aid if the drawings to narrow down the area where the fault lies. Then break that area down smaller, and do the same, narrowing it down again. The drawings should tell you (I admit they are not the easiest to follow) what is connected and what isn't with the fuses pulled.
I agree, it makes sense to look at the start relay and especially the starter motor connection as both could be susceptible to water. Disconnecting the fusible links will again help to break it down. If still present when they are disconnected it would be on the heavy cabling. If it does disappear, you can put your meter from Batt + to the one that has the drain and see what that feeds.
I agree, it makes sense to look at the start relay and especially the starter motor connection as both could be susceptible to water. Disconnecting the fusible links will again help to break it down. If still present when they are disconnected it would be on the heavy cabling. If it does disappear, you can put your meter from Batt + to the one that has the drain and see what that feeds.
I have tested across every single fuse in the truck and it's not pulling across one of those. Makes me wonder about the starter solenoid. Like I have already said. I don't think the drawings will help. It's not seemingly coming form a component in the vehicle. It's something that's been added or where something has worn thin. In that case I can see it at the battery terminal but so far not in any of the rest of the loom as it were. I will start with the big connections like the starter and 24v change over and see where that gets me. But so far none of the smaller elements of the wiring have shown anything.
I will split the bridge cable between the two batteries at some point and see if the drain goes. If it does then it shows it's going into the fused loom somewhere. If I can still see it across the main battery then, I'll know it's in the big stuff. But not got the car at the minute.
I will split the bridge cable between the two batteries at some point and see if the drain goes. If it does then it shows it's going into the fused loom somewhere. If I can still see it across the main battery then, I'll know it's in the big stuff. But not got the car at the minute.
Sounds like you've got a plan there Chris. I wish you luck with it.
OK so we're getting somewhere.
Total drain is 0.13 amps. What I did today was split the three elements of the cross charging cable from batt A, the fusible black link and the fusible grey link. There was 0 amps down the black. 0.03 down the grey which feels sort of right for a car at rest and yep, 0.1 amps going through the cross cable. One end of that is connected to the aux battery of course to carry charge from the alternator but the other end has a myriad of connections into the changeover relay, starter, main battery etc. When I get a moment I will drop the starter feed and see if it's leaking through there to start with. But without taking off the cables one by one, I can't tell yet. It could be leaking across the changeover to earth for example. These readings are taken all with both batteries completely disconnected.
But it's clearly not one of the standard vehicle systems fed from the slave battery.
The search moves forward..
Total drain is 0.13 amps. What I did today was split the three elements of the cross charging cable from batt A, the fusible black link and the fusible grey link. There was 0 amps down the black. 0.03 down the grey which feels sort of right for a car at rest and yep, 0.1 amps going through the cross cable. One end of that is connected to the aux battery of course to carry charge from the alternator but the other end has a myriad of connections into the changeover relay, starter, main battery etc. When I get a moment I will drop the starter feed and see if it's leaking through there to start with. But without taking off the cables one by one, I can't tell yet. It could be leaking across the changeover to earth for example. These readings are taken all with both batteries completely disconnected.
But it's clearly not one of the standard vehicle systems fed from the slave battery.
The search moves forward..
On the scent and closing in fast by the sound of it Chris.
Yes, closer. But there is a difference between finding where it is against WHAT it is. I might narrow it to say the starter motor but I will still need to find the 'why'. Is there any way I can use coloured smoke for fault finding?
I generally find copious amounts of black, grey or sometimes white smoke tends to help establish location of electrical faults.
As can be seen here:-
http://youtu.be/WkDCS8xeobg
The smoke is excellent in attracting attention to the fault which can further be confirmed by a loud buzzing sound and very bright light…
I'd say this is probably not quite what you had in mind…
As can be seen here:-
http://youtu.be/WkDCS8xeobg
The smoke is excellent in attracting attention to the fault which can further be confirmed by a loud buzzing sound and very bright light…
I'd say this is probably not quite what you had in mind…
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Well, I think we may have got to the bottom of this.
I took the cover off the changeover relay and whilst pondering noticed a crimped terminal coming off the input side. Yes, from the main battery supply. So I pulled on it to see where it went and found this
Then I tugged a bit more and go this
And after about an hour of slashing and yanking I ended up with this and seemingly no drain anymore.
It's a mixture of old mobile phone gubbins and the reaminder of a ghetto blasting stereo. I had already removed the subwoofer and amps. Can't believe this lot was still in there. There's even a battery pack. Most likely the drain was an effort to charge the dead batteries. it was tied into the OEM loom all over the place.
I took the cover off the changeover relay and whilst pondering noticed a crimped terminal coming off the input side. Yes, from the main battery supply. So I pulled on it to see where it went and found this
Then I tugged a bit more and go this
And after about an hour of slashing and yanking I ended up with this and seemingly no drain anymore.
It's a mixture of old mobile phone gubbins and the reaminder of a ghetto blasting stereo. I had already removed the subwoofer and amps. Can't believe this lot was still in there. There's even a battery pack. Most likely the drain was an effort to charge the dead batteries. it was tied into the OEM loom all over the place.
