Hi all

As I started adding more electronic accessories to my Runner I decided I needed a cleaner way of tapping into the power source. I searched and found some good write-ups on FJ, TT, and ExPo I decided to do one for us 4Runners.

This does take a little bit of handy work with such tools like a Dremel and a drill but not overly complicated.

*** DISCLAIMER: Always wear safety equipment when performing such work. Disconnect your battery before you start your work. Before you reconnect the battery tripple check your work. I take no responsibility in what you do with this write-up or whatever happens to you and your vehicle. ***

Items used

• (1) Blue Sea 5026 ST Blade Fuse Block 12 Circuit $35.89
• (1) Goldquest 3-Way 40A AGU Fused Power Block Fuse Holder 54020 (only needed 2-way but the 3rd comes in handy later) $5.50
• (1) 40A AGU Glass Fuse 5 PK $1.75
• (1) 12V 30/40A SPDT Relay $1.95
• (1) Add-A-Circuit $5.99
• (1) 20ft 8ga Automotive Wire (Primary Power Wire) $14.81
• (1) 100ft 14ga Automotive Wire (Secondary Power Accessory Wire) $10.19
• (1) 20ft 18ga Automotive Wire (Add-A-Circuit Extension Wire) $5.99
• (2) 5 inch "L" Brackets
• and various quick disconnect and connectors

Diagram

Basically the idea is to have a fuse block that I can access either constant or accessory/on 12volt power.



Location

This write-up is related to 4th Gens so previous Gens your mileage may vary. I chose to put the fuse box in the engine bay near the battery. Now some have mix feelings about this such as exposure to water, mud, etc... I originally had some aftermarket power connects right at the battery terminal so to me this would be the same. On other forums some do it this way as others do it right on the firewall inside their cabins just above the footwell. I personally couldn't find any room to do it there so in the engine bay it went. The pros of locating it in the engine bay is that it's easy to access, the cons are you have to run your positive through the firewall boot for each accessory that's inside your cabin.



Blue Sea 5026 ST Blade Fuse Block 12 Circuit

From other forums this fuse block seems to be the chosen one. It's a marine product for the boating industry but as you can see it's not water resistant. You can have a myriad of connections styles but I chose 6 circuits on constant power and the last 6 on Acc/On key states. I've also seen other fuse blocks by other manufacturers with built-in relays but I haven't seen any reviews on them so I don't know how well they are. Note: I've also read that 12 circuits on one draw may be too much load so splitting in two circuits is probably a good idea.



Reconfigure for 6 Constant & 6 Acc/On

Make sure you're careful when dremeling your brand new $40 fuse block. You don't want to have an oops moment. ;) The first thing is to cut the middle bar so circuits 1-6 and 7-12 are seperated. Next will be to cut the negative wing terminals and discard them. The negative side of the post will no longer be negative as you will create a jumper to the 1-6 terminals for positive connection. When creating your jumper use an 8 awg power wire. I stripped the wire bare and applied 2 disconnects at the end. If your disconnects are smaller than mine then there's no need to have the wire bare. I also had to use a washer on one of my disconnects because it was a lot larger than the connecting screw and the disconnect size was all that I had.



Reconfigure Complete

All done!



Install Brackets

To mount the fuse block I used 5" L or shelf brackets from Lowes. I used the existing bottom holes from my Runner and will have to drill two new holes an inch and a half above that for the top screws. The fuse block sits right on top of the bottom part of the bracket and screws in using one set of the predrilled holes. For the top part of the fuse block you'll have to drill two more holes on the bracket. I also mounted the relay just underneath the fuse block using one of the predrilled holes. The reason I mounted this way is that you have to give room for the hood shocks to lower and close with out hitting the fuse block. This option works out well and it's very sturdy.



Configure Relay

Sorry I didn't have a better picture of the relay but basically if you look at the diagram above you can see how the relay is set up. The idea is that you have a constant power source from the battery, a connection to the fuse box, a trigger such as Acc/On to tell the relay to make the connection and a ground. The middle terminal 87a is not used. For more info about relays visit The12Volt here.



Add-A-Circuit

For the relay trigger on I used a mini Add-A-Circuit you can get from Autozone. As many before had mention, you can tap into a power source using an existing fuse which makes everything look clean. The Acc/On I chose was the 4Runner's CIG fuse. So when the key is in the Acc or On position, it triggers the relay to turn on circuits 7-12. No unwanted battery drain if you happen to leave an accessory on while the vehicle is turned off.



All Done

And my first candidate for connection.. Cobra 75 WX ST.




Keep Runnin!