Assume you're talking wiring with an 8 year old here...
I have a stand alone LS swap harness that needs 12v power hookup. Some wires are for constant battery power, some are for keyed on 12v.
I bought 2 of these cheap fuse blocks off eBay so I could wire one to a toggle switch and one directly to the battery.
My question is this: is this the right type of fuse block? I see no provisions for ground? Is that okay since I assume the items I'm hooking up are already ground through the harness? Or is that a bad assumption?
You're good. You're only fusing the positives, all the grounds in the harness just go directly to ground lugs
In reply to Patrick :
Thanks Pat! I was hoping you'd see this and chime in.
I have my datsun wired the same way. One block to ign power(toggle switch to relay to fuse block) and one off battery. Been that way for 6 years
In reply to Patrick :
Didn't realize I would need a relay for the toggle switch to the fuse block. Have any input on that? Size of relay?
In reply to Scotty Con Queso :
Patrick will be able to give a better answer, but I am guessing a normal 30 amp relay should be fine. It's there so you don't have the full load going through the switch. Also, won't have to run as thick of a wire to the switch that way.
If I remember correctly you're swapping a Colorado truck. Why use a toggle switch ? Using the key power wire from the truck to operate the relay is way more elegant. I'm no toggle switch hater but there are slicker ways to do things.
In reply to Cousin_Eddie (Forum Supporter) :
Agree, if the truck can do it already go that way. I went with a relay to be safe, and because i love running tiny switched wires and using a relay close to the need to minimize weight of long runs of thick wire and also safety factor for rubbing wires and such. The less big wire running everywhere the better i feel. Tbh i think i used an early gmt400 fuel pump relay, but any 30 amp relay will do.
Cousin_Eddie (Forum Supporter) said:
Using the key power wire from the truck to operate the relay is way more elegant. I'm no toggle switch hater but there are slicker ways to do things.
Especially when the throttle hangs WOT in a School zone, you don't want to be flailing around trying to find multiple kill switches. Key off, done.
^^What these guys said, otherwise you're on the right track. Orange wires to +12V constant, pink to +12V switched. Go with a bigger fuse block than you need so you have empty slots available later, in case you want to add accessories down the road (lights, gauges, etc.) Label/diagram the crap out of everything, you'll thank yourself later if you ever need to troubleshoot!
So should I just find any wire that gets 12v from key on and wire it to the positive side of the new fuse panel?
Scotty Con Queso said:
So should I just find any wire that gets 12v from key on and wire it to the positive side of the new fuse panel?
I'd still run a relay between, so keyed ignition wire to 86, battery power (maybe through a high amp fuse?) to 30, ground to 85, and output to the fuse panel to 87.
Edit: for getting power to the relay, I suspect there will be a post on your fuse box that already has a fuse or fusible link in line from the battery that you can use. Just need to follow your positive cable from the battery over to the under hood fuse box. I have a GMT800 fuse box laying around, I can probably take a picture later, if you want.
Another wiring for dummies question. I got this 1990s Volvo 940 2 speed fan from the junkyard. I've heard great things about them. The biggest thing being that they have the relays self contained. Below is the diagram on the relays. The pcm is have is wired to switch fan 1 and fan 2 at centain coolant temps so I can easily wire that. My question is how do I lower these? Red wire directly to battery? Or do I need a relay between the battery and the fan relays?
Looks like red is battery, blue and white wires are your two triggers and the other two are your fans.
Stampie said:
Looks like red is battery, blue and white wires are your two triggers and the other two are your fans.
Plus a fuse in there somewhere either on the battery feed or on the fan output. A fuse is the difference between "why won't my fans work?" and "why is my car on fire?"
I don't like to run battery power straight to a relay, but I'm not sure how other people feel about it. If you can find out how many amps the fans are supposed to draw, I'd put a fuse between the battery and the red wire that is reasonably larger than the draw is supposed to be, just in case.
I was wrong to assume that a fuse was a given. Especially since I was driving a F150 once where an unfused wire caught the dash on fire.
Scotty Con Queso said:
Assume you're talking wiring with an 8 year old here...
I have a stand alone LS swap harness that needs 12v power hookup. Some wires are for constant battery power, some are for keyed on 12v.
I bought 2 of these cheap fuse blocks off eBay so I could wire one to a toggle switch and one directly to the battery.
My question is this: is this the right type of fuse block? I see no provisions for ground? Is that okay since I assume the items I'm hooking up are already ground through the harness? Or is that a bad assumption?
In a "race car" type build is it better just to have one bigger fuse block?
Maybe I am asking what is the best way to do what Scotty is trying to do? One bigger fuse block that also has some relays on it?
Last wiring hurtle to overcome. I don't know what to do to wire the stock fuel pump with the stand alone relay. I think all I need to do is wire the "fuel pump load" from the stand alone relay to the power wire to the trucks fuel pump? Maybe any help here. First two pics are the stand alone relay and the horrible stand alone directions. Third pic is of the trucks stock fuel pump wiring.
More info. This is the bottom of the stand alone relay. The green wire at the bottom is pin 9 "fuel pump relay control" and the other is ground. So if I understand correctly, one side of the relay needs to go to constant power, and the other needs to go to the trucks fuel pump wire? Just not sure what the trucks fuel pump wire is?
If it hasn't changed in a while, I think GM uses gray for power to the fuel pump. So, that'd be the output from the relay. The green wire should be the trigger wire, it sounds like.
In reply to Scotty Con Queso :
Hello, sorry I think we have the same type of harness, will you have the manual to see what each cable is for?
AngryCorvair (Forum Supporter) said:
Cousin_Eddie (Forum Supporter) said:
Using the key power wire from the truck to operate the relay is way more elegant. I'm no toggle switch hater but there are slicker ways to do things.
Especially when the throttle hangs WOT in a School zone, you don't want to be flailing around trying to find multiple kill switches. Key off, done.
Why are you WOT in a school zone? ;)
(I know, old thread)
