dual batteries

cost will vary, who installs it, what battery etc.
Run 6 mm wire from battery, 12 volt sockets are best avoided for this sort of thing.
Cheers Lyndon

Its not that difficult providing you have some basic skills, patience, and an adequate supply of beer. If you know how to solde, fit a battery tray, understand basic wiring, and so on, you're on your way. You can buy an isolator, such as a Redarc unit for example (not the only one available but many have had excellent results with them), and a power socket from most auto parts suppliesr. Get the correct size cable, which guys on here will inform you of soon, I can't remember the size. Appropriate connectors, etc.

Since your vehicle has 2 batteries already, you could just isolate one from the other with an isolator (maybe $200 including a bit of extra wiring). Some owners have done this (check lcool forums).
The wiring to the rear will be enough to run the engel but it is connected to the ignition (needs key to work) when you really want it connected directly to the second battery. Probably need another cable.
You add a third battery in the engine bay or one in the cargo area. Either way you are looking at somewhere between $500 and $1000 including the battery, I guess.
I haven't mucked with the 2 cranking batteries in mine - I prefer to have a third battery in the cargo area which can also then be removed from the vehicle easily when camping.

I'm not particularly bright with electrics, but I bought a kit, the battery, battery box, and with the help of some diagrams other than in the kit box, I did everything myself. I installed the second battery in the back of the Mazda, ran the wiring, fixed the solenoid and so far everything looks and runs properly. Took me a bit of time, but I'm glad I did it because if something goes pear-shaped and I'm out bush, at least I will know what was hidden where.
ps change the cigarette socket thing for something more substantial; mine kept blowing. I now have the fridge plug wired to the battery with proper connectors and an in-line fuse.
Good luck.

Second battery is essential to avoid being stranded with a cold fridge but a car that won't start. Esp if auto trans. And esp if you are on your own or don't have jumper leads. At least you could console yourself with a cold drink while waiting for help to arrive (although after 3 or 4 days the drinks will have warmed). Good case for a solar panel.

A back up battery (deep cycle) easy to install. It doesn't need to be complicated or expensive. A manual system with a heavy duty switch (from a marine shop) works well provided you remember to isolate when you pull over for a prolonged stop, and reconnect when mobile again.

Use cranking strength cables between the main battery and the secondary unit. Use heavy duty cables to run aft to the fridge - voltage loss is your enemy. Use Engel connectors. Cover cables with that black plastic ribbed protective stuff to avoid chafing and short circuits. I have fuses at each end of the cable run.

I don't know about the TD 100 series but in the V8 (LX470) I had to move the power steering pump away from the front R side of the engine bay where the second battery naturally wanted to be put.

The Optima yellow battery charges quickly and lasts for ages. In addition, because it is sealed it can lie on its side (so will keep working even when you have rolled the vehicle) or be deployed in the cabin (no acid burns on the passengers).

Brentos,

There are several options to choose from.

As you have a cradle for a second battery, this is probably a good option, provided you can find the right place to install it in the engine bay.

Another option is to install a portable battery system in the rear which can be removed if you desire. This battery should be charged by the vehicle alternator.

In either case, an Isolator should be included to keep the primary and secondary batteries separated from each other.

Have a look at Vehicle Electrics topic for in depth information.

Bill.

Hi Brentos
Do not use the standard power socket in your vehicle to run your fridge, the moment that you turn your vehicle off and take your keys out of the ignition, all power will be lost to your fridge. Do yourself your biggest favour and buy yourself an Engel ASpan fitting and wire it with good quality wire back to you auxiliary battery.

Unscrew the tip from the end of the power lead, then push and screw in the fitting for a 100% fit, that will not let you down on the roughest of tracks. If you do not know how the ASpan works, your Engel supplier will gladly show how.

Cheers

Stephen

Yours is one of the easiest to fit as a DIY kit.

Fridge wiring approx $95 using 6mm2 twin core.

DIY kit approx $295.00 excl. the battery.

Use a MRV70 105 a/h approx $195.00.

The existing plug is too thin and switched via the acc. Best to run a new circuit.



Regards

Derek.

Derek,
Interesting fuse system there on your battery photo, low profile would be very useful especially it battery boxes.

Regards
Shane

brentos,
Use an AGM Deep Cycle battery.
Anything else is just a cheap compromise if you need optimum battery performance.
Do it yourself with a "battery isolator" between the AGM and the Cranking battery.
Remember to put a fuse (or circuit breaker) at each (+) battery terminal.
I personally would use much thicker cable than that previously mentioned to get zero Voltage drop.

Use a dedicated power circuit for the fridge.

Mainey . . .

hey guys thanks for your info
its much appreciated ill look into it further

feel free to keep your ideas and feed back coming

regards

brentos

hey there again

can anyone explain how to wire up for dual batteries
or post a diagram of the wiring set up

thanks guys
regards
brentos

Hi brentos, i didnt read all your reply's (have had enough of reading for one night) but agree with troll, standard wiring and plugs just dont cut it for running fridges, they will over heat and burn out, anderson plugs are very popular these days for good reason.......the cost of dual battery system vary considerably, you could go the cheap option which is a $120 solarnoid from supercheap and add the cost of the battery and wiring which is easy to install yourself or go for a full battery management system which is alot more expensive but this option is automatic so its a case of install and forget, it will manage itself, the previous option you will need to remember to turn it on and off, i went for a thumper pack from arb which is basically a versitile second battery that can also be used to jump start and charge phones,camera's etc and can be removed from the vehicle to run the fridge at camp but is about the same price as a battery mangement system.