Japanese Import Two Batteries

[Larry1 Lurker Find all posts View Profile Close Larry1]

Hi

I have recenlty bought a second hand Diesel Prado (year 2000, TX model), oringially imported from Japan. It has two batteries under the hood. My auto electrician tells me that both batteries are required to start the engine. I was hoping to use just one of these batteries to start the engine and the other for running a fridge and install an isolator between the two batteries. The auto electrician says no can do as both batteries are required to start the engine. Is he correct?

Thanks in advance for your responses.

Larry1

[RogueAussie Senior Member Find all posts View Profile Close RogueAussie]

Re: Japanese Import Two Batteries

Larry, Where are you from (could help with answers to questions, just update your details ===>).

My first question would be, what size batteries are they? Maybe, for some bizare reason there a 2 smaller units hooked up together that will produce the required voltage to kick the starter over. Can 2 be swapped out for one?

[Schaffer Addicted PP Member Find all posts View Profile Close Schaffer]

Re: Japanese Import Two Batteries

The standard should be for a single battery to start and the second should be an auxillary. Connsting these across the positive terminal there "should" be some sort of isolator where the two postivie terminals are connected to seperate terminal studs but connect internally through the isolator when the voltage levels of the crank exceeds a fixed amount.

You could try to disconnect one and see what happens. The one of the passanger side of the engine bay should be the crank battery so try disconnecting the other and then try to start the vehicle. Make sure you isolate the cables so you can not get a short to earth occuring.

[Wil Senior Member Find all posts View Profile Close Wil]

Re: Japanese Import Two Batteries

Surely this is as simple as disconnect one battery - try and start and see what happens. Then re-connect it, disconnect the other and try again?

interested to hear the results.

[HeathNZ Junior Member Find all posts View Profile Close HeathNZ]

Re: Japanese Import Two Batteries

I believe the "cold weather Packs" were an option in north Japan and had two batts fitted so the cold weather wouldnt mean a loss of power (cold = low power) and the vehicle could still be started. I wonder is a piranaha system or simillar could be inserted bewteen the batts to seperate them...

[croozza Avid PP Poster! Find all posts View Profile Close croozza]

Re: Japanese Import Two Batteries

The set up your talking about is for cold weather climates, as they require extra power to start the motor in extreme cold weather, you can disconnect one battery and rewire to suit a proper dual battery set up, it is a bit of a fiddle, but worth it in the end.

[Larry1 Lurker Find all posts View Profile Close Larry1]

Re: Japanese Import Two Batteries

Thanks for your responses. I have since checked it out with two seperate auto electricians. They both advised that it is better to leave it set up as it is currently i.e. have two batteries to start the car. Otherwise I run a real risk of the car not starting in cold weather e.g. at the snow. I have run an 8 B&S cable with anderson plug to the boot where I have a battery box with a battery. There is an isolator between the first two starter batteries under the bonnet and the battery in the boot. That suits me fine as I only need the 3rd auxillery battery for camping trips. The third battery sits in a battery box secured in the boot and there is a cargo barrier in place in case it turns into a missile in a crash situation!

[ozwapet2 Advanced Member Find all posts View Profile Close ozwapet2]

Re: Japanese Import Two Batteries

I'm not sure why auto elecs would give that advice ( if your batteries are the same CCA rating as those fitted to Australian spec vehicles.) If Toyota spec'd only one battery for here, you should have been OK splitting them. I've had mine in probably the coldest conditions you'll find in Australia, ( top of Mt. Hotham in mid winter ) no problem starting.
Some other makes ( eg Holden/Isuzu Jackaroo ) do have two batteries as standard here on their diesel models, because of the high compression of the engines.
Anyway moot point now, you've put the third battery in, so you'll be fine.

[ChampN Lurker Find all posts View Profile Close ChampN]

Re: Japanese Import Two Batteries

Hi my friends...

I am a new member from Denmark, Europe.
Here in Europe the Prado diesel always comes with 2 batteries. The diesel engine requires more power to start up than the gasoline engines. So it will not be a smart thing to disconnect one of the batteries. Not eaven in contrys with warmer places than Asia or Europe.

My own car is a 2001 Toy Landcruiser 95 - 50th anniversary - limited edition european version
Pictures can be seen on this link:

http://forum.ih8mud.com/90-series-tech/ ... -90-a.html

The one on the picture is not mine, but its 99% the same, with the only difference that mine is with automatic stepdown gearbox and 10 seats.

It's nice o be with U on this site...

Best regards

Tommy

[croozza Avid PP Poster! Find all posts View Profile Close croozza]

Re: Japanese Import Two Batteries

Hi my friends...

I am a new member from Denmark, Europe.
Here in Europe the Prado diesel always comes with 2 batteries. The diesel engine requires more power to start up than the gasoline engines. So it will not be a smart thing to disconnect one of the batteries. Not eaven in contrys with warmer places than Asia or Europe.

My own car is a 2001 Toy Landcruiser 95 - 50th anniversary - limited edition european version
Pictures can be seen on this link:

http://forum.ih8mud.com/90-series-tech/ ... -90-a.html

The one on the picture is not mine, but its 99% the same, with the only difference that mine is with automatic stepdown gearbox and 10 seats.

It's nice o be with U on this site...

Best regards

Tommy

Hey ChampN
Yes you are right about the twin battery set up, however, in Australia, the diesel model Prado comes with only one battery, this is due to the warmer weather conditions, the vehicle in question is a second hand import, (brought in before the diesel model was sold new in Australia), so it has the twin battery set up, it would not cause any problem if it was converted to start on one battery.
In Australia, we like to have a dual battery set up, so that we can run accessories like fridges (as it can get very hot here), winches, ect.
So basically a twin battery set up is when 2 batteries are set up in parrallel, and a dual battery set up is when either battery is used independently of each other however both set ups will charge both batteries at the same time.

[ChampN Lurker Find all posts View Profile Close ChampN]

Re: Japanese Import Two Batteries

Hi my friends...

I am a new member from Denmark, Europe.
Here in Europe the Prado diesel always comes with 2 batteries. The diesel engine requires more power to start up than the gasoline engines. So it will not be a smart thing to disconnect one of the batteries. Not eaven in contrys with warmer places than Asia or Europe.

My own car is a 2001 Toy Landcruiser 95 - 50th anniversary - limited edition european version
Pictures can be seen on this link:

http://forum.ih8mud.com/90-series-tech/ ... -90-a.html

The one on the picture is not mine, but its 99% the same, with the only difference that mine is with automatic stepdown gearbox and 10 seats.

It's nice o be with U on this site...

Best regards

Tommy

Hey ChampN
Yes you are right about the twin battery set up, however, in Australia, the diesel model Prado comes with only one battery, this is due to the warmer weather conditions, the vehicle in question is a second hand import, (brought in before the diesel model was sold new in Australia), so it has the twin battery set up, it would not cause any problem if it was converted to start on one battery.
In Australia, we like to have a dual battery set up, so that we can run accessories like fridges (as it can get very hot here), winches, ect.
So basically a twin battery set up is when 2 batteries are set up in parrallel, and a dual battery set up is when either battery is used independently of each other however both set ups will charge both batteries at the same time.

Hey Croozza
Thanks for the Down under update.
I see the difference off dual and parrallel set up.
Here in Europe we allso like to run accesories. But here we just add a 3. batterie.
Have a nice day my friend.


Best regards Tommy

[Derb Senior Member Find all posts View Profile Close Derb]

Re: Japanese Import Two Batteries

Hi Larry1. We have a large number of jap-import Prados in NZ with twin battery set-ups. The Toyota dealerships commonly convert them to a single (large) battery system when the original batteries go tits-up. You would have to have some seriously sub-zero weather to have starting issues with one good battery. My diesel prado sits outside at work in some pretty mean overnight frosts and hasnt let me down yet (I always buy the largest battery I can fit in the Tray). One down side of twin battery set-up (in parallel) is that if one battery goes down, you should really replace both batteries. Hope this helps. Cheers, Derb.

[benwalden Junior Member Find all posts View Profile Close benwalden]

Re: Japanese Import Two Batteries

ive been wondering the same thing and havent touched them for the very reason everyone here is talking about. As cold weather is more common down our way. good to know that a twin batt set up is possible with not alot of drama. i looked at the ARB systems when i was last in Australia but didnt end up buying one due to the cold weather here. cheers Ben

[twopointsevenone Lurker Find all posts View Profile Close twopointsevenone]

Re: Japanese Import Two Batteries

My KZJ95 had two batteries stock. I live in coldish Switzerland, but it's not nearly as cold as Scandinavia or Siberia, etc.

I converted my car to single starting battery and aux battery.

The original setup is strange. The left battery has a ground wire to the body. The right battery doesn't, but instead it has a ground wire that goes into the motor, presumably to the starter and then elsewhere. I found it pretty creepy actually. Sow when you simply remove the right battery, the starter's ground wire will dangle in the air. This can't be good!

What I did was to use the original wire that connects the two positive battery terminals to connect the left battery's ground to the "starter ground" wire that goes into the motor.

Once that is done, the car is converted to single battery starting. Now the right battery tray is free for an aux battery. To work in the cold, the starter battery needs to be a good one. I prefer AGM but it's a matter of opinion.

For the aux battery, I use a Protecta isolator and new wiring with an 80A fuse near the isolator. I hooked the aux battery's ground terminal to the repurposed former positive wire.

This has worked for three years or so without problems.

[Derb Senior Member Find all posts View Profile Close Derb]

Re: Japanese Import Two Batteries

Hi twopointseven. Doesnt matter a damn if the 2nd battery bolts straight on to the engine for an earth. As long as somewhere along the line the chassis is also connected to the engine via a good earth cable. The more earth wires on a motor vehicle the better! If you removed your 2nd battery and the earth wire was floating around in the breeze, as long as it didn't get caught in rotating or live components, does'nt matter if it bumps and rattles against kit - it is at the same potential anyway. The terminal to worry about is a live posative wire floating around. Hell, that will make things a bit exiting for a while. Cheers, Derb.