Some aftermarket light wiring help

[Nick C.]

I'm installing my new kc's on thursday and I need some help. I'm going to draw power going into the relay from the battery (by connecting it to the battery terminal). Is this a bad idea?

Now I need power going into the switch, can I splice from the same wire I'm using to get power to the relay? where is the best/easiest place to get this power from? I want my lights to come on when I hit the switch in the truck and at no other time, ignition on/off doesn't matter to me.

If there's any blatant ignorance being displayed please ignore it. All help is appreciated.

 

[Bill Kemp]

Relay is connected to battery (w/fuse).
Switch wire can also be connected to battery.
Only drawback, IMO, is that you can leave the lights on when you turn the veh. off & run down the battery.
For fog lights I like to connect the switch wire to the "always hot" red(I think) wire going into the wiper motor. That way lights can be on any time the veh. key is on.
For driving lights I use the high beam headlight wire. I only use the driving lights when useing the high beams and this way I dont have to dim the headlights & then push a switch to turn off the driving lights. They just go off w/high beams.
Different strokes for different folks.

 

[Nick C.]

Exactly what I needed to know. I don't think I'll forget and leave them on. At 350,000 candlepower each I hopefully will see them before I get inside. Thanks for the help. If anyone else had suggestions...

 

[Alec]

I agree with all that has been said.

Make sure both links are fused (probably 5 amp and 15 amp.)

 

[Nick C.]

When I run the power wire from the battery I use the positive or red side of the battery correct?

I've never done car wiring before so bear with me.

 

[Alec]

uhh, yeah.

 

[Bill Kemp]

Heres a site that has some good info on wiring lights.
http://catalog.com/susq/other/auxlamps.htm
Go to "MY stuff" or something like that and check out the wiring guide also.

 

[Nick C.]

I used to be an electrician and understand wiring in houses just fine. I'm sure this is a different thread topic but in house wiring both wires black and white while called hot and neutral are both "hot" wires at all times. They complete the circuit so to run power to a receptacle you need both wires. Obviously in car wiring you don't need both to get a power to a switch or lights or stereo. So what is the purpose of the negative terminal?

thanks for the link Bill stuff like that helps out.

 

[aldive]

Ground, Here you are dealing with DC and not AC.

 

[Nick C.]

Right, it's just weird trying to convert in my mind.

 

[Alec]

Remember, DC is simpler than AC. Everything is a big loop. In the case with a relayed light set, it's 2 loops intersecting at the relay.

 

[Nick C.]

which now explains why the lights MUST be grounded to work...that completes the loop.

ahh haaa

 

[rikguy]

Is it ok to use the negative battery terminal as a ground? My aftermarket driving lights aren't working and I beleive its the ground. I have to run a ground from the switch and another ground from the lights.

 

[Bill Kemp]

Not only OK but its the best way.

 

[Nick C.]

The best way? Can you explain...it's the best way to ensure a good ground?

I didn't want to run another wire all the way to the battery so I grounded mine to the metal bumper...

 

[Bill Kemp]

The metal bumper is eventually grounded to the battery by way of the metal body and battery cables. Screws &connectors can rust and the ground can end up being less than 100%. So the best way is to ground to the battery. Do I do it? Not always cause I dont want to run the wire either so I take a short cut. However if you have a problem it is usually the ground connection.
On the interior, where its not subjected to the elements, body grounds are the way to go.