Single 'Master Power' Relay? Why not?

[Stuarto49]

I recently acquired a very nice 85 FJ1100, red and white.  After some carb work it is running quite well.

In addition to a GPS mount with wiring, I installed a digital voltmeter in the left hand upper cowl, and due to many 30-year old connections it reads about 10 V until running.  Once underway it displays 14.1 V so I am confident that the charging system is OK.  I tapped into the signal fuse for these supplies.  I've been reading about relay upgrades for the ignition feed, and separate relay upgrades for the lighting. 

I am thinking that I could install a single relay to bring full battery voltage 'up front' to the triple fuse block, via 14 or even 12 ga wire.  I'd use a key-on circuit under the seat (already found for my upgraded running/brake/turn LED units)
This single circuit would feed all 3 fuses with much closer to 12V.  Anybody try this?  Any downsides with this scheme? 

Thanks, 

Stuart in Richmond, VA

[FJ1100mjk]

Stuart:

I did what you're proposing, but fed full voltage off the battery, to a six fuse accessory fuse block. One of the circuits, has the voltage gauge to it. The gauge, shows nearly (short a couple of tenths) the same voltage as a multimeter's that is placed across the battery's terminals. Both at idle, and when the engine runs in excess of 4,000 RPM. I also have my relayed headlight circuit on the accessory fuse block too. Works well.

[jscgdunn]

Here is an option for this....I replaced my homebrew mess with it:

http://easternbeaver.com/Main/Wiring_Kits/Fuseboxes/3_Circuit/3_circuit.html

[Nova]

A fused accessory power block is always the way to go. You can buy one off the shelf or make one yourself on the cheap if you have some basic wiring skills. The components are not expensive.

The graphic here helped me immensely when I made mine: http://www.canyonchasers.net/shop/generic/relay.php

[ct7088]

Use your own relay and add the three fuse accessory block from eastern beaver or some other supplier. http://easternbeaver.com/Main/Elec__Products/Fuseholders/fuseholders.html

[ct7088]

Control the relay with the main key switch and wire to power original and added fuse block. Be sure to check the regulator/alternator connector for melted or corroded conditions. The two wires are red and brown two pin connector replace it with something more modern. The bad connection causes the alternator to run at a higher voltage which has ruined batteries. The relay bypassing the key switch will also help this problem.

[ribbert]

....I've been reading about relay upgrades for the ignition feed, and separate relay upgrades for the lighting. 

I have been adding electrical accessories one by one for years:

                   HID headlight conversion
                   Auxiliary driving lights
                   Heated grips
                   GPS
                   Electronic chain oiler
                   TPMS
                   Indicator tell tale
                   Brake light modulator
                   HUD/GPS speedo
                   Heated vest connector
                   Auxiliary power outlet
                   Double USB plug
                   Air horn
                   4 relays
                   Soon to be added LED dimmer and on/off switch.

                  ....and all the associated relays, wiring, control boxes, switching and wiring.

....and the wiring is now like a dogs dinner. I have never had a problem with it but if I ever needed to trouble shoot it on the road (or in the workshop for that matter) I would be stuffed. Everything is black wire and nothing is labelled and by now there are so many wires I have lost track.

I was embarrassed by one of my own wiring jobs recently into re wiring the FJ.

I have bought (and waiting for it to turn up on my door step) one of these:

   

http://www.fuzeblocks.com/

It has a few cool features, everything is powered through the one relay, moving the fuses L or R will change that terminal from switched to unswitched (and vice versa) and it has diodes to smooth out voltage, a problem I actually have, losing settings on one accessory when another one fires up.

I will post up pictures when installed.

Noel