Battery Going Flat

[harrythomas]

Hello All,

I have a 2007 Patrol GU 6 and if I do not use it for a week or so the battery tends to go flat.

After it is driven it reads 12.8 volts and while it is parked it drops about 0.2 volts per day. Would this be normal or does it indicate that there is a problem?

Thanks for your help,

Harry.

[AB]

Definitely a problem mate, slow drain or not holding charge.

I'm hopeless with electrics so hopefully someone else can jump in but I would be looking at what accessories have you added to the main battery?

I have a similar issue and mine is related to the egt gauge wired directly to battery rather then accessory power.

Definitely look at what extras you have added to the battery and hopefully someone else can help out.

[happygu]

What do you have connected Harry?

I presume that you have dual batteries ... first step may be to disconnect the batteries from each other and see which one has the voltage leak....

You can measure for current draw too when everything is supposed to be off, and then pull fuses until you have none at all

[my third 256]

go to a battery shop and get them to test it with their metre's
to see if batteries are in good condition
and they usually dont charge for service as they might get a sale out of it

[harrythomas]

Definitely a problem mate, slow drain or not holding charge.

I'm hopeless with electrics so hopefully someone else can jump in but I would be looking at what accessories have you added to the main battery?

I have a similar issue and mine is related to the egt gauge wired directly to battery rather then accessory power.

Definitely look at what extras you have added to the battery and hopefully someone else can help out.

Thanks AB, I am hopeless too and I am thinking that drooping 0.2 volts per day was too much. Only extra I have added lately is a winch but I have isolated it.

[harrythomas]

What do you have connected Harry?

I presume that you have dual batteries ... first step may be to disconnect the batteries from each other and see which one has the voltage leak....

You can measure for current draw too when everything is supposed to be off, and then pull fuses until you have none at all

I did have dual batteries but they both were stuffed and I have just replaced one and the other one is not connected but I will replace it soon. I tried checking all the fuses with a multimeter and can only find a slight draw on the car radio when everything is of. May be a job for the auto electric.

[harrythomas]

go to a battery shop and get them to test it with their metre's
to see if batteries are in good condition
and they usually dont charge for service as they might get a sale out of it

Yes, good advice I will be taking it to the battery shop.

[AB]

I did have dual batteries but they both were stuffed and I have just replaced one and the other one is not connected but I will replace it soon. I tried checking all the fuses with a multimeter and can only find a slight draw on the car radio when everything is of. May be a job for the auto electric.

Sorry mate I'm confused, do you have 2 x deep cycle batteries "2 x second batteries"?

Do you have a battery management system going to the second battery(s)?

Do you still have the second battery connected to the main battery?

As mentioned above, disconnect that if still wired up to at least eliminate that side.

[harrythomas]

Sorry mate I'm confused, do you have 2 x deep cycle batteries "2 x second batteries"?

Do you have a battery management system going to the second battery(s)?

Do you still have the second battery connected to the main battery?

As mentioned above, disconnect that if still wired up to at least eliminate that side.

Sorry for the confusion AB. I will try to make it a bit clearer.

When I purchased the vehicle it had duel batteries. The main and a secondary. There is no management system for the second battery. A couple of months ago when the batteries would not turn the motor over (the start of winter when it always happens) I took it to an auto electrician who found both of the batteries stuffed. I replaced the main battery and removed the secondary so I only have a main battery for now. Bloody costly to replace both in one hit. My plan is to replace the second battery down the track. After the new battery was fitted I found that if I did not use the vehicle for a week or so the new battery would go flat.

As I know very little about the electrics I thought I would ask the question here first but It looks like I need to take it back to the auto electrician and make sure the new battery is all right first then go from there.

Thanks,

Harry.

[K1W1]

What do you have connected Harry?

You can measure for current draw too when everything is supposed to be off, and then pull fuses until you have none at all

This is very good advice and probably how the Auto Sparkies will track it down

[P4trol]

Another way is to disconnect all the small wires from the battery (with everything off).

Touch them individually to the battery. Any sparks indicate current draw. Although not scientific, a rough guide is

small orange sparks - small current draw
Larger orange sparks - more
Small blue sparks - more current
Larger blue sparks/audible click lots.

Now don't laugh at me, but it is a quick and easy way to work out which wires are worth a second look with a multimeter.

Another option is to put in a solar panel. A small type that plugs into the cigarette lighter might do. Any larger panels would need a solar regulator.

Another option is to refit the battery with another cranking battery. It will last twice as long then.

(and of course these options are merely masking the problem).

[K1W1]

If using the above method and yours is a petrol engined Patrol observe the usual precautions for welding on carburettors

[harrythomas]

I have been through all the fuses K1W1 and only found a small current on the radio/cd circuit which I think is normal.

I have no small wires left on the battery P4trol but thanks for the “rough guide” regarding the different sparks. Good for future reference. There was three small wires on the main battery when I purchased the vehicle but after this problem started I have tracked them back. They all went back into the cab then went nowhere so I have removed them. I think there has been some backyard wiring happening on this vehicle so I seems there is more to find yet.

[harrythomas]

Monday afternoon I discovered this

48671

behind the dash jammed between the all the wiring and the firewall. All the wires on it were cut off it except the power inlet which was hard wired into a circuit which remained live when the key was turned off.

It is now in the rubbish bin and the battery has held it charge since then.

Thanks for all your advice in trying to sort this out.

Harry.

[happygu]

Monday afternoon I discovered this

48671

behind the dash jammed between the all the wiring and the firewall. All the wires on it were cut off it except the power inlet which was hard wired into a circuit which remained live when the key was turned off.

It is now in the rubbish bin and the battery has held it charge since then.

Thanks for all your advice in trying to sort this out.

Harry.

Great work Harry, and good persistence too....

[graeme1969]

What is it?

[my third 256]

on board phone kit for nokia phone

[harrythomas]

Great work Harry, and good persistence too....

Thanks mate, and a few more grey hairs.