Dual Battery Install With Painless Wiring Kit

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I was asked in another thread to post pics of my dual Optimas and battery kit #40103 from Painless Wiring. The yellow is a 34D/78 and the red is the 34R reverse pole for the FJ-80. The Painless system allows you to connect and switch two batteries from the cab via a 3-way toggle and two indicators lights. The red top is installed as primary and the yellow is aux. The switching allows for the:

- Switch in the middle and no indicator lights. This setting is just like OEM...the left (red) battery is the only one in the charging circuit. In this position the yellow battery is totally out of the loop (isolated) and will not be charged (or drained other than by just sitting).

- Switch to the left and a green indicator light. This setting brings both batteries into the charging loop. This setting only works when the ACC/IGN is on.

- Switch to the right, red indicator. This setting brings both batteries into the charging loop. This setting works with key on or off. OPTION >>> You can also wire the system so that the aux battery is isolated as the only battery IN the circuit when on this setting (this is how mine is currently wired.) This is ideal if you want to winch off of the deep cycle battery only or if you want to isolate the aux battery and save your primary to bail you out.

FYI if you buy the Painless kit, it does not come with LEDs, rather standard red and green bulbs. I bought the LEDs and used them instead. I made the cables myself using 1 gauge wire and 1/0 copper ends from O Reilly's. The red wire in a soft flex is hard to find and pretty pricey. The boots are Ancor (yes, I ran out and am missing one) and are available at marine stores and places like Gander Mountain. The ends were soldered lightly and crimped before heating the boots. The positive lead to the aux is run under the front crossmember. The aux negative is grounded to the frame by the motor mount. The system has two 10 amp fuses that I chose to install into the engine bay fusebox so they look OEM. The wiring is wrapped up tidy in flex covering and run into the cab through the rubber firewall grommet. Solenoid is installed on the charcoal canister bracket.

EDIT>>> I canned the Painless LEDs and toggle in favor of a hybrid DPDT switch I made from two Cole Hersee switches.

Optima sends these batteries to their dealers with special plastic spacers snapped on top to protect the posts. If you can get two of these, they also will snap onto the bottom of the battery and raise its level up in the box about 1.5" so you can use OEM bracketry. You may also have to use a die tool and cut some additional threads onto the tie-down rods.

Painless Kit runs about $100 and has good instructions. Wiring and all the other stuff willl be about $40. Its a :banana: job and takes a couple hours.

Works for me.

Jim

p.s. The "front posts" on these batteries are misleading. They are not posts into the battery, but thin leads running from the top posts under the raised surfaces on the top housing. As such they are not able to handle much amperage draw. They are okay for attaching fog lights or electronics, but not a winch (they melt).
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Gee - that engine still looks clean Jim! ;)
 
Jim--

Is this the weatherproof kit or the non-weatherproof kit?

I have the weatherproof kit awaiting install in my garage.

Thanks for the write up.

Getting wires next week for this.

Cheers.
-onur
 
Thanks Jim for the info. I am going out and doing this same set up in the next week or soo. Thanks again for the write up and pictures. Chans
 
beno said:
Jim--
Is this the weatherproof kit or the non-weatherproof kit?
-onur

Mine is teh standard kit, but I cannot image what the they do to the kit to make it weatherproof. I used marine-grade connectors and heat shrink tubing and see no ay weather or water could affect it. I bought my first one from 4 Wheel Parts for $100 and the second new in the box on eBay for $60.
 
You didn't relocate the washer bottle? I thought that was required.

Vince
 
97cruiser said:
You didn't relocate the washer bottle? I thought that was required.

Vince


he did, you are looking at the coolant overflow bottle witch stays.
 
Ah yes , :o silly me
 
Hmmm, looks like Steppenwolf in the tune box.....a little "Magic Carpet Ride"?
 
Jim,

I really like the way you've mod your 80 and the clean installation you've done. I will install this in the near future as I've already installed in the second OEM battery tray.

Do you think a rear heater switch can be modified to work as the dual battery switch? It would look so much more OEM than the PW switch.

Where is your center diff lock switch?
 
97 FZJ80 said:
I really like the way you've mod your 80 and the clean installation you've done. I will install this in the near future as I've already installed in the second OEM battery tray.

Do you think a rear heater switch can be modified to work as the dual battery switch? It would look so much more OEM than the PW switch.

Where is your center diff lock switch?

Thanks. I hate aftermarket switches but had never really given much thought to making an OEM switch work as a battery selector.....sounds very cool though. Electronics is not one of my strong suits, but I'll gladly copy yours if you figure it out. :D My CDL is in the upper center bank, left of the emergency flashers. I relo'd the Toyota glass breakage sensor from that spot over to the upper left of the mirror panel. I will be installing two OEM light switches in the vertical spots there below it, one for the front lights and one for some utility lights I will eventually be installing on the back and underneath.
 

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