Isolator

Probably can't go past an advertiser on this site. Derek Bester @ Link He not only has all the right gear but also the right answers at the right price. I have no interest or affiliation with him or his business. I'm just a happy and satisfied customer.

IMHO if you only have a dual battery in the car the ABR (Derek Bester) at www.sidewinder.com.au would be the place to go. If you have a trailer with batteries which also require charging then Rotronics rotronics.com.au would the place to go. Both people are very helpful. I chose a Rotronics system because I have an off road trailer with batteries and it appeared to me their system appeared to manage the charging of all batteries successfully. Mind you the Rotronics system is expensive and requires a good 8 hours work to set up.
Richard

Rotronics recommended the MH10 on a Prado same as yours which I owned in the past. Derek would probably recommend the Redarc, which is a cheaper option with a good reputation. I mounted the isolator on the drivers side firewall near the plate. That way it was easy to run the cables around the firewall and it was not far from the wiper motor, which was the source of IGN power I used for the Rotronics. Rotronics provide fusible links for use at each battery to give you good short-circuit protection.

If your in the budget priced Redarc/ABR/ARB mechanical solenoid range, then 'upgrade' away from the old technology Mechanical solenoid system and the look at a MATSON Electronic Isolator.

Link: http://www.matson.com.au/images/98500fitting.pdf

If you desire the best performance then ROTRONICS independent system.
In between there is the Piranha and Rotronics Electronics systems.

Mechanical solenoids use much more precious 12v battery power to operate, whereby Electronic systems use only a miniscule ~0.05v.