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Discussion Starter · #1 ·
Hi

Apols for starting another thread on this topic. I recently picked up a sweet T4, seller warned me about battery drain and to hook up a trickle charge (not ideal, practically speaking). All been going well for a month with no additional charge applied. Then found a dead (well almost) dead battery on Tuesday, just had enough to let me open the doors (shaved handles, key fob only) to get the kids car seats before complete drain.

I spoke to the local Electrical technician previously about drain, they had checked it for the seller prior to sale, they could find nothing obvious although said it was slightly higher than normal but not enough to concern them. The Van has AccuAir Suspension which works of an Auxiliary battery & also lights and DVD player (but not used either yet). The AccuAir suspension self regulates when driving (which is great), the auxiliary battery is charged from the main battery, so there is some drain when being driven but this is not in use when engine is off (I think).

I also have an Alarm and Tracker fitted plus Stereo, so again there is some drain but I was using the Van daily. From the other Threads I will check the Alternator too. However, I am faced with either working through each item and potentially removing DVD, Lights, tracker, alarm maybe even suspension, but all that seems stupid since it was part of the appeal.

One other option speaking to a friend who is a TVR owner (they love shaved doors), is to attach a key fob operated battery isolator. e.g. it cuts all power to battery once parked up.....does anyone have any experience of this? Any thoughts appreciated (maybe an insurance risk, may allow me to remove the alarm etc).....

Cheers!
 

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I love electrical problems... they're the most fun! <sarcasm>

I'd start by removing any aftermarket electronics; stereo/sub/alarm (watch your insurance if you do this) for any dodgy wiring, twisted-tape joints etc. Do them one at a time for a couple of days, you should be able to cut the power or remove a fuse without removing the whole thing. If it turns out the drain is one of those, it could be bad wiring, a short or a faulty product.
 

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Hi mate.

Its always better to find the source of the drain and rectify if possible than adding another aftermarket idea to get around it.

Start by narrowing down the circuit(s) in question, you will need a mulitimeter and knowledge of how to read the draw in amps from the battery, with key out of the ignition. Pulling each fuse in turn should eventually show a drop in reading.

How big is your main battery in ah?

If theres nothing you can do about the aftermarket equipments draw you could either fit a bigger capacity battery. Or power some of your non vitals ie. Stereo, suspension ect from a secondary leisure battery.

All the equip soon adds up to a higher than 1amp draw, at that rate you really NEED to run the van everyday without fail or the battery is doomed.

I have had a similar situation with mine and it had a .80a draw.
 

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Agreed with Mat. Get a meter and go at it one step at a time. Also, make sure the battery is good to begin with. If it has had a history of going flat it is probably on its way out, especially if it hasn't been recharged properly time after time.
 

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I agree with the above post ... if the battery is on its way out, you'd be going to a lot of trouble for nothing trying to find out what's draining it.

Battery lives vary from 2 to 10 years, and depend on a huge number of factors, e.g. quality of manufacture in the first place, being correctly sized for its intended use, whether it was ever partially flat when temperatures dropped below freezing, whether it was ever run completely flat (seems this has already happened at least once), and many other factors.

You can get battery testers that supposedly test the CCA rating of the battery (Cold Cranking Amps). Batteries for diesels are intended to be > 500 CCA, but that's when they're brand new. Usually after as little as a year, a 500 CCA battery is already down to about 400 CCA, and this carries on dropping at a rate that depends hugely on the type of use the battery is put to. Short journeys every day are about as bad as long journeys four times a year.

Once you've determined that your battery is good or replaced, pulling fuses to find exactly what's draining the battery is a pretty obvious and simple exercise.
 

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Discussion Starter · #6 ·
Thank You Gents,

I believe the Battery is new, I will check that. I had a technician confirm the draw is 0.85a, he wasn't overly concerned by that. We have been using the van most days but not always on the longest journey, ignorantly I've not been monitoring it because I assumed that would be enough to keep the battery charged.

I will buy a meter and work through each item.

Thanks, will let you know when/if I find the offending item!

Cheers
Graham
 

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It still doesn't rule out the battery being damaged by having been left in a state of discharge. You should also check the alternator output.
 
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