Switch Power- Source?
Moderator
Joined: Jan 2001
Posts: 56,973
Likes: 2,731
From: Virginia
What is the total wattage of the lights, and how do you want them to work, i.e. do you want them to come on with the headlights, or have a separate switch for them? Do you want them to work with or without the ignition being on?
Moderator
Joined: Jan 2001
Posts: 56,973
Likes: 2,731
From: Virginia
100w at 12v = 8.3 amps. The best way to do this is mount a bosch type foglamp relay under the hood near the battery. Hook a inline fuse rated around 15 amps to the battery +, and then run this to the relay contact. Come out of the other relay contact and run to the lights. Use at least a 14 gauge wire for these connections.
For the coil of the relay, hook one side of the coil to a metal ground near the relay. Connect another wire to the remaining coil terminal, and run this all the way inside cab to your switch. Come out of the other side of the switch with another wire, and run this to the fuse box. Go buy some little gizmos they call "fuse taps". This will let you hook the wire from the switch into the fuse box. Pick something that is only on with the ignition on, such as the radio or possibly the blower motor. That will let the lights only work with the key in run, though if you hook it to the radio fuse, they might also work in acc position too.
For the coil of the relay, hook one side of the coil to a metal ground near the relay. Connect another wire to the remaining coil terminal, and run this all the way inside cab to your switch. Come out of the other side of the switch with another wire, and run this to the fuse box. Go buy some little gizmos they call "fuse taps". This will let you hook the wire from the switch into the fuse box. Pick something that is only on with the ignition on, such as the radio or possibly the blower motor. That will let the lights only work with the key in run, though if you hook it to the radio fuse, they might also work in acc position too.
Thread Starter
|
Elder User
Joined: Dec 2002
Posts: 793
Likes: 0
From: SoFla
"fuse taps"- that's something I need to know... I diagrammed out your explanation and it is doable. So, am I supposed to add the 8.3 amp draw to whatever I fuse tap it to- and make sure I do not go over a certain fuse rating. Say a 15amp fuse for the radio- but what does the radio draw 11amps- so add these 8.3 and 11 (estimated) which is 19.3 so I need at least 20amps- Is my thinking on the right path here.
getting ready for shuttle lauch 6-15-09
Dutch
getting ready for shuttle lauch 6-15-09
Dutch
Junior User
Joined: Aug 2006
Posts: 75
Likes: 0
From: Slimeattle, Weakynton
Here is a diagram with relay hookups that I drew for somebody else.
You could hook up the switched power to something that only comes on when you turn the ignition. With a relay hookup you don't have to worry so much about the current draw of what you hook up the switched power to, because the relay coil only uses about 150 milliamps.
The picture I drew is for an eight light system, but one of the relays there, is for two lights.
You could hook up the switched power to something that only comes on when you turn the ignition. With a relay hookup you don't have to worry so much about the current draw of what you hook up the switched power to, because the relay coil only uses about 150 milliamps.
The picture I drew is for an eight light system, but one of the relays there, is for two lights.
Thread Starter
|
Elder User
Joined: Dec 2002
Posts: 793
Likes: 0
From: SoFla
Trending Topics
Mountain Pass
Joined: Mar 2009
Posts: 123
Likes: 3
BTW- Ran into a snag; obviuosly need to run wire assembly from engine bay into the cab. I have a 3/8" male-female connector (rectangular) that needs to find it's way. Should I drill this diameter hole- or bore out to this diameter an existing hole which currently is passing wires into the cab?
Cranks
Cranks
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Moderator
Joined: Jan 2001
Posts: 56,973
Likes: 2,731
From: Virginia
It's already made up on the underhood end? I guess you have already checked if you could undo this end and route the wire through the firewall from the inside, if the connector is going to end up being on the inside.
Otherwise, I guess a 3/8 hole is going to be required. They are a little bit expensive, but you can go to the store and buy what they call a "uni-bit". It's a stepped looking drill bit that makes a beautiful hole in sheetmetal.
Otherwise, I guess a 3/8 hole is going to be required. They are a little bit expensive, but you can go to the store and buy what they call a "uni-bit". It's a stepped looking drill bit that makes a beautiful hole in sheetmetal.
