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Discussion Starter · #1 ·
I know this has been covered a fair bit - I've read several threads and picked up some good ideas. Just wanted to run this past everyone and see if there's anything obvious I've missed T:

Problem is this: my battery's going flat over a week or so standing on the drive.

While my bus was in the paintshop over the winter the battery died on several occasions. No-one really worried too much about it - everyone concerned just assumed it was cos it had been sat around a lot in the cold.

Got it back, battery dead after a few days. Full charge, lasted nearly a week this time. So I bought a new battery.

Which is also now dead, after a bit over a week...

So either both batteries are duff, or I have a leak. I'm going to charge both batteries up. I've cleaned all the battery terminal connections and replaced one that looked a bit skanky. Had a look at the battery earth - looks fine, nice and clean. Can't do much more because the riveted plastic shroud around it makes it hard for me to even get an open ended spanner on there.

With one of the batteries freshly charged I'm gonna disconnect the -ve feed and put a multimeter between that and the battery. That should hopefully show a current drain (if it doesn't I'm really stumped!). Drain established I'm then gonna pull fuses to see if I can isolate the circuit that's the cause of the trouble, starting with the Webasto engine heater (which has never worked and I haven't got round to fixing).

If none of the fuses show anything the only other thing I can think of to check is the earth strap on the starter motor.

Anything else I can check fairly easily?
 

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It may be the Auxillary coolant pump running on after you have parked up. Fuse 19 protects that circuit if I remember rightly. Search on here about the pump and battery drain, I'm sure you'll find some useful threads related to that problem T:
 

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Discussion Starter · #3 ·
It may be the Auxillary coolant pump running on after you have parked up. Fuse 19 protects that circuit if I remember rightly. Search on here about the pump and battery drain, I'm sure you'll find some useful threads related to that problem T:
Thanks. Forgot to mention, I'm pretty sure that's not the problem (been scrabbling around underneath a fair bit recently trying to track down bellypan rattles, and no pump-related noises).

Does the 2.4 even have the auxiliary pump...?
 

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Discussion Starter · #5 ·
Thanks for the replies...

Some progress. Battery drain measured at 180-190mA. That figures - it's roughly what I worked out to be based on battery's capacity and length of time to drain completely.

Started pulling fuses... got to fuse 21 (interior lights, clock, radio)... BINGO! Zero drain.

So I figure the stereo is the prime suspect? It works without the key in the ignition...is this right, or part of the problem?
 

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Thanks for the replies...

Some progress. Battery drain measured at 180-190mA. That figures - it's roughly what I worked out to be based on battery's capacity and length of time to drain completely.

Started pulling fuses... got to fuse 21 (interior lights, clock, radio)... BINGO! Zero drain.

So I figure the stereo is the prime suspect? It works without the key in the ignition...is this right, or part of the problem?

That's the problem right there, you probably need to switch the live and ignition wires round, as the head unit will draw a small wattage even on standby
 

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Swap the red and yellow on the iso connector, most have bullet and butt connectors to let you do this. Should come on with the ignition A:T:
 

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Discussion Starter · #9 ·
Thanks for all the replies.

Ignition feed didn't run to stereo; instead live feed was split and run to live and switched inputs on head unit. So stereo independent of ignition but permanently drawing 0.2A. Doesn't sound much, but enough to drain the battery in a week or so...

I've tried a temporary fix wired as it should be. Drain now 10mA (sounds about right to me) but can't run stereo unless ignition is on. Which is a pain in a camper ;)

So before I put my plan B into action (wire ignition feed through switch in one of the dash blanks), is there another fix? I want to be able to turn the stereo on independent of the ignition, but obviously the existing solution is drawing too much fom th battery. Suggestions welcome...
 

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Our stereo is wired "wrong" so it works without the key in, it doesn't appear to drain the battery. I assume it's either very meagre in its standby power draw or it does something clever like have its own internal battery to maintain the settings. Anyway, I offer "buy a new stereo" as an option :)

I keep meaning to rewire it to the leisure battery to remove the risk of too much tuneage resulting in an inability to start the engine, you could do that and make sure you plug the hookup in on the drive regularly.

Or the switch sounds like a good idea. I've got a couple of spare early switches kicking around somewhere if you want one...
 

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just keep the ignition switched live in place as is so in normal driving it turns off when you take the key out, and then run another live to that input from a switch on the dash so when youre in camper mode you flick the switch and hey presto tunage!

To protect your battery from running flat you could put a timer relay in place of the switch which gives you a max of one hour of music and then automatically shuts it off.

PS you may require a diode in line with your ignition switched live if you do this otherwise it could back feed and turn your ignition on nT:

Another idea, assuming yours is an early t4 would be to fit a later ignition barrel as that way the stereo would be on until you remove the key not until you turn the van off?
 

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Discussion Starter · #12 ·
Our stereo is wired "wrong" so it works without the key in, it doesn't appear to drain the battery. I assume it's either very meagre in its standby power draw or it does something clever like have its own internal battery to maintain the settings. Anyway, I offer "buy a new stereo" as an option :)

I keep meaning to rewire it to the leisure battery to remove the risk of too much tuneage resulting in an inability to start the engine, you could do that and make sure you plug the hookup in on the drive regularly.

Or the switch sounds like a good idea. I've got a couple of spare early switches kicking around somewhere if you want one...
Thanks Mike. Your stereo must be more posherer than mine, or something. I've just replaced it and the new one also flattens the battery, so new stereo not a favoured option!

Was considering a stock switch, but Maplins have illuminated red switches that'll fit in a switch blank - and I'm thinking a gert big glowing red switch will help remind me to turn it off :) My T3 ran all the interior lights and stereo off the engine battery and it was (mostly) not a problem...
 

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Discussion Starter · #13 ·
just keep the ignition switched live in place as is so in normal driving it turns off when you take the key out, and then run another live to that input from a switch on the dash so when youre in camper mode you flick the switch and hey presto tunage!

To protect your battery from running flat you could put a timer relay in place of the switch which gives you a max of one hour of music and then automatically shuts it off.

PS you may require a diode in line with your ignition switched live if you do this otherwise it could back feed and turn your ignition on nT:

Another idea, assuming yours is an early t4 would be to fit a later ignition barrel as that way the stereo would be on until you remove the key not until you turn the van off?
Hadn't thought about the diode... good point!

As for the ignition barrel, I'd assumed there'd be a whole different loom to go with the later barrel. Doesn't it have an 'acc on' position? That'd presumably need a separate live feed :*
 

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Some stock switches have lights in too, although not huge red ones :)

Haven't (fingers crossed) managed to flatten the battery with actual stereo use yet, but possibly only because I'm a bit paranoid about doing so.
 
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