Page 1 of 1

Bongo Battery Drain...

Posted: Sat Aug 18, 2018 11:34 am
by rosss
Hello all,

My bongo seems to have some kind of battery drain. The troubles started when i left it over winter, didn't drive it for two months and the battery flattened. I got a new battery then and since then if i leave it for one week, it's gone dead... If i drive it around a bit, and then try to start it again in the next few days it's fine... it's only if i leave it about a week that it goes dead.
I've got a multimeter and checked the Amps running from the negative terminal to the connector when there's nothing on and it's giving me a reading of about 0.5 on the 10A setting....
I removed all the fuses in the bonnet fuseboxes one at a time and it didn't do anything to the reading... did the same with all the fuses down by the drivers door... same, nothing made any difference.
I removed the starter motor wire from the positive terminal... that didn't make a difference...
Kindof wits end here... I think i want to test that it's not the alternator's fault ... so i need to disconnect that/?
any other clues appreciated!
Thanks!
Ross

Re: Bongo Battery Drain...

Posted: Sat Aug 18, 2018 12:05 pm
by g8dhe
Did you remove the 100 Amp (Blue) fuse from the battery terminal - needs unbolting, or if your a diesel then the Fusible link connection that is also bolted to the terminal arm. There are several unswitched circuits that could be the cause, primary one that comes to mind is the alternator output and its field coil, starter motor and the above fusible link to the glowplugs, these all have feeds from the terminal arm and its fuses.
A 0.5 Amp draw is certainly going to flatten the battery over a few days to a week, if you haven't already found them the Wiring Diagrams are on-line here Image

Re: Bongo Battery Drain...

Posted: Sat Aug 18, 2018 12:26 pm
by rosss
Aha... ok thanks (and yes it's a 2.5 diesel) - no, the only fuse i didn't remove was the 100A one... i'll try that next.

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 10:51 am
by rosss
Good morning...
So, I unbolted and removed the 100A fuse but it wasn't that - the multimeter was still showing the drain.
However I then removed the bottom cable from the three connections to the positive terminal and the drain was gone.
It's a 95 TD, it has three connections to the positive terminal. One is the fusible link to the glow plugs - seems fine, the other is connected to the fusebox with the 100A fuse etc in it... that also seems fine - but what is the third connection? the bottom one? if i remove just that connection then the drain drops down to nothing...
I checked out the somewhat insane looking wiring diagram in the manual but that connection didn't feature in it at all as far as i could tell - there appear to be only two connections coming from the positive terminal in the diagram...
hmmm... all tips gratefully received!
Thanks.

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 10:56 am
by g8dhe
Do you have a leisure Battery with a Split Charge Relay fitted ? Otherwise best to follow the cable along and see what it feeds it doesn't sound like original wiring.

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 12:24 pm
by rosss
Thanks Geoff,

I do have a leisure battery, plus one of the original (i think) RF-V Camper Kitchen Units... basically just a fridge, a sink and a cooker along one side at the back - all electrics turned off... to be honest i'm not sure it's ever been connected.. as in, I thought it only worked from hook-up.
I don't think I have a Split Charge Relay though i'm not totally sure what i'm looking for... can't see anything that stands out under the bonnet - this lead and the lead from the positive terminal on the leisure battery - both just join all the other tubed electric leads and head off down under the van.
it's pretty difficult to follow them any more accurately without taking it all apart... I'm guessing from what you've said though that the issue is to do with the leisure battery / camper unit.
I've put a link showing the connector and also just a general one of under the bonnet in case anything jumps out.
Thanks!

images:
https://www.dropbox.com/s/6h4c38g1xz5vo ... 1.png?dl=0
https://www.dropbox.com/s/gpr49vdd6d1gc ... 2.png?dl=0

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 2:36 pm
by g8dhe
Ah no that heavy duty cable is the feed to the Starter Motor itself, there is no fuse or anything in that. The starter motor is then controlled by a separate relay driven from the Ignition switch, it sounds like you may have a parasitic draw from something touching the starter motor cable or the contacters in the starter motor are being bridged and allowing a current to flow, not a common problem I have heard of before but not impossible.

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 3:47 pm
by rosss
Aha, ok thanks... I just realised that i said i checked the starter motor cable in the first entry of this thread... i didn't - it was the fusible link...
I went surfing a while back, buried my key, and then when i came back to the bongo i inserted it without removing the grit duh... so, for months, turning the key in the ignition was a bit gritty...
just wondering if this could've shorted something somewhere in there that's showing up as this? Guess that's a long shot... I'm gonna try taking a look at the starter motor but i guess i'm gonna have to consider turning the beast over to someone who knows what they're doing...
thanks for all your help.

Re: Bongo Battery Drain...

Posted: Tue Aug 21, 2018 4:00 pm
by g8dhe
Can't see that grit/sand in the ignition switch would cause a parasitic current drain, but worn / burnt-out starter motor contacters will cause intermittent starting problems - you just here a click as the solenoid pulls the contacts together, but as they are burnt out nothing happens - but the residual muck could - in theory - cause an excessive current to be drawn, but as I say its not a problem I have heard of before, but can't rule it out!
Check the connections to the starter motor and make sure there is no muck or road spray affecting the connections (remember there always live and unfused!!!).

Re: Bongo Battery Drain...

Posted: Wed Aug 22, 2018 5:48 pm
by rosss
Thanks again.
I haven't had any problems starting at all (apart from when the battery's dead.)
It's definitely the starter motor cable that's causing the drain.
Having a look at the connections they're very clean... but they do look a bit rusty. Thinking of trying to remove the bolts and put new washers on... reckon that's got a chance? otherwise i guess it's maybe get the starter replaced :(

https://www.dropbox.com/s/ua419p5yaz49z ... 0.JPG?dl=0
https://www.dropbox.com/s/eohy2x8bgjfel ... 1.JPG?dl=0

Re: Bongo Battery Drain...

Posted: Wed Aug 22, 2018 6:18 pm
by rosss
Took off the bolts cleaned them up - put them back on... no joy... same drain...

Re: Bongo Battery Drain...

Posted: Wed Aug 22, 2018 6:38 pm
by g8dhe
Sounds from what you describe that it is in the Starter Motor or the Contacter itself then.
See Youtube for how to get at the contacters https://www.youtube.com/watch?v=5pnySma88gY