I need to does thsi mod to my car. I have some parts that I have not installed yet do to waiting to get more stuff son I can tune at one time. With this mod i will not have to worry about a tune and I can feel like I have done something.

I will go the route that Gadd has done.

 

OK boys, checked out my idea - using the existing FP fuse to implement this mod. Turns out reality is not as simple as the wiring diagram. The problem is not that there isn't sufficient power available in the under dash fuse box. This box is actually called the "joint box" by Mazda. No the problem is that it is not very user servicable. It is kind of like a multi-layered circuit board in there. Once I removed the joint box and popped off the back cover, I quickly decided I did not want to try my idea at all:







So I went the Gadd route. Nice thing is that Mazda left a beefy unswitched positive power wire in the second to last (unused) fuse slot right next to the fuel pump relay (these are the very heavy gage black wires visible in the picture below). There is no need to run a new wire from the battery to power the Big Blue wire, you only need to add a fuse and a connection to the Blue wire. I snipped the Big Blue wire and crimped a bullet connector to it. Then I drilled a 1/4 inch hole straight through the unused side of the fuse connector, from the top, to allow my female spade connector to fit. I crimped the female onto a heavy gage wire a few inches long and dropped it down through this hole in the top, and installed the fuse. On the backside, I installed a bullet connector onto this wire. Finallly I plugged the two bullets into a female-female bullet coupler and closed it all back up:



I used the 20 amp fuse from the under dash joint box, to plug into my new fuse location next to the fuel pump relay. Looks very clean and there was no need to run a new wire to the battery:



Before I did this modification, my fuel pump readings were not quite as low as Dale's. But I did get 1.1 volts out of this modification:

before:

WOT / no accessories: FP reading = 12.7 volts
WOT / headlights and AC max: FP reading = 12.5 volts

after:

WOT / no accessories: FP reading = 13.8 volts
WOT / headlights and AC max: FP reading = 13.6 volts

 

so i decided to go the "GADD" route as well. i basically screwed myself over. i cut the wire in the wrong direction, meaning i cut it extremely short to the relay to the point that i cant get anything on there. for some reason i thought i had to have the wire coming from the wiring harness as long as possible when it was the complete opposite which i now understand. sucks to be me.

with that being said, can some please explain to me how to de-pin the blue wire from the green relay so that i can fix my mistake without making the situation worse then it already is.

thanks in advance

 

How short is it on the FP relay? If you have a quarter inch or so, you can probably strip it and solder a new piece of wire to it to get you back in business. Then slip a piece of shrink wrap over the solder joint and shrink it down. If it is too short to do this, you may need to de-pin the relay as you suggest. I haven't tried that, but if the relay unplugs from the top, then it implies the wires on the back side are crimped to female pins that the relay plugs into.

Maybe somebody who has unplugged the relay can comment on this?

 

no such luck. its pretty much flush with the plasic. no soldering if i wanted to. it pretty much just needs to come out and a new one put back in from what ive seen.

i tried pulling it out from the bottom of the fuse box but am getting no where fast and am afraid i am going to end up breaking something if i persist.

 

i got it!! if anyone wants to know how to de-pin this **** let me know. not as hard as you would think just gotta know what to do. all the pulling and pushing in the world wouldnt help if i didnt figure it out. should be able to pick up some parts tommorow and be good to go.

what can i say frustration can be blinding sometimes.

 

OK give...

 

umm... how do i post pictures on here?

 

I'm betting it's a little tab that's holding the pin in.

Insert a jeweler's screwdriver, and out it comes . . .

:-) neil

 

sounds about right, kinda has a trianglur shape on the backside of the spade connector holding it from coming out. just gotta bend the spade connector to enough to get past it, then pull from the back of the fuse box. i was planning on posting up some pictures for those want a visual but that about sums it up.

to get it back in is the exact opposite, push spade back in, bend spade ends and your basically done.

not hard just gotta now what to do.

 

I'm glad we see eye to eye, now
https://www.rx7club.com/showpost.php...7&postcount=87
^just for ref. There is a reason you won't see the stock "joint box"

 

OMFG! You are a madman. I'm not sure that your chassis is rigid enough though...

 

Since you redid your wiring, would you happen to have this... https://www.rx7club.com/showpost.php...10&postcount=1 or maybe know where I can locate one?

 

^sorry bro...most unneeded pieces went in the trash. Ray Crowe should be able to get it.

 

It's part of the wiring harness, so I don't think you can buy it separately.

 

I tried to do this today using the "Spare" Fuse holder.

Mine has a 20A fuse in it, labelled "TEL" Its a jap car...do we know what this is?

cheers

Carl

 

find a jap manual...might be some help.

 

Dunno what it is. But this does explain why our US cars have a beefy wire supplying half of what is needed for this mod.

Without knowing what your JDM fuse is doing, I would leave it alone. There should be one more vacant position in that fuse box. You'll need to use two female spade connectors, one for the relay side and one for the power side. You could jumper the power side with a heavy gauge wire to one of the beefy black wires already there. This would still be cleaner than running a whole nother separate wire to the battery.

 

Yeah but that wouldnt be fused either...think im just gonna run a separate wire.

 

Nah, I was saying put another fuse in the empty slot next to your JDM "TEL" fuse. I was suggesting that you could get power for this new fuse with a short length of heavy wire connected to one of the heavy black (unfused and unswitched positive) wires that are inside the fuse box. No need to run new wires to the battery.

 

There are no empty fuse slots! lol but thanks for your help anyway.

 

Ah, I see. On our US boxes, there are two empty slots one of which is powered, though unused. I was assuming this was used for TEL in your JDM car. Apparently they put as many fuse slots as they needed for the JDM version so yours are all in use.

Separate fuse with wire to battery then I guess.

 

The history impaired among us, and/or those just too young to know about it, may not realize that using 'jap' as short for 'Japanese' is considered a racial slur.

Some may contest this due to the context (not referring to people) but the context really doesn't matter. Best just to not use it.

 

^agree. I use JDM.

 

Easy as pie did this in about 10 minutes mmmmm more voltage...