Hi all
I have been looking around for answers in the posts on how to due this I have came up with this is it right will it work need help.

I want to have the dome light in my camper shell come on when I use my Keyless remote to unlock the doors.

I have lights mounted under the vehicle that automatically light when the doors are manually unlocked, or remotely unlocked with a keyless entry key fob.

Can I tap into that wire with no reduction in this safety margin of the factory wiring?

Or should I use a relay to apply 12V to the dome light in my camper shell.
Did I get this right here is I’m lost?

To add a relay I need to
attach fuse to + terminal of battery,
run wire from fuse to one of the relays "contact" run wire from remaining contact pin dome light. remaining wire to ground.

That completes the current supply wiring.


Now I run a wire from the +12v switched side of the (lights mounted under the vehicle) circuit to one of the relay's "coil" pins and the reaming pin to ground.
That completes the activation of wiring.

The Dome lights will now illuminate with the lights mounted under the vehicle
I hope
Thanks Dog

 

Hmmmmm Dogface, some of that post sounds familiar.

Yes, that is the correct way to do it.

Having said that...
depending on the design of the circuit for the under vehicle lighting, and the wattage of the dome lamp you are adding, you might get by just tapping into it. 2-3 more amps is possibly OK.


Is the dome lamp connected to +12v now? (unclear in your post)

If you want to use the camper dome lamp when parked (camping?) you will need additional wiring.

Good Luck... XLT_D

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Thanks XceLenT Driver

my post dose have alot of info from other posts just wanted to do this right.

The lights mounted under the vehicle are cheap fogs from Wal Mart 35 watt $20 Lites with a 20 watt relay.
From the post Under Vehicle Lights

No shell or cap is not here yet on order just wanted to have the wires in when its installed. here is link to the shell http://www.carryboy.com/index_fiber.htm
Then click on the Super F Shell.

What additional wiring will i need when parked or should i add another dome light for when it parked(camping?) want it to be right.
Thanks Dog

 

Dogface,

A dozen people may have a dozen ways of doing it "right" and a dozen more ways that will work. So it's good to ask around, get some ideas, and do what you like.

The two 35watt lamps in your under vehicle lighting circuit are only drawing about 6 amps. If you have a 20 amp (not watt) relay then you have enough "reserve capacity" to run the new dome lamp from that circuit. (assumes the dome lamp is 20-35w)

Since you are starting from scratch, I would run +12v and ground wires into the bed from the battery. Use 14 ga. wire (minimum) and a 20-25 amp fuse on the +12v wire close to the battery. Connect your new +12v wire to dome lamp's switch and the ground wire to the dome lamp's common (or ground).
This will allow you run the dome lamp at ANYTIME and will give you flexibility if you want to install other lighting or accessories inside the shell.

Now, the switched +12v from your under vehicle lighting circuit relay can be attached to the dome lamp circuit (be sure to connect it to the lamp side of the switch). This will illuminate the dome lamp when your under vehicle lights come on.

Good Luck... XLT_D

 

XceLenT Driver

Thanks for help

I run a wire from #86 Relay to the lamp side of the switch of the dome lamp (.(Off side of switch) )

I also removed the 20 amp relay replaced with a 30 amp relay.
Is this a over kill

Thanks Dog

 

Dogface,

I think we're close here.

Pin #86 of most "automotive type" relays is one of the coil or actuator wires (along with #85).

You need to connect to pin #30 or #87 of the relay used in your under vehicle lighting circuit. One of them connects to some +12v source and the other connects to the lamps.... Connect to the pin # going to the lamps!

The "Off side of the switch"?
I think you mean the side of the switch connected to the dome lamp not the side connected to +12v.
If so YES.
If you swap that connection, no damage, it just won't light with the under vehicle lights (cause the switch is Off!).

Upgrade of the relay to 30 amps overkill???

Yes, but... it won't hurt anything.

Don't do that with fuses though, always go lower in value if you have to replace one (untill you can get the proper value).

XLT_D

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XceLenT Driver

You are the best I think it’s finally sunk in here.

My under vehicle lights relay is like this # 30 Load (lights). # 87 (+) Battery with fuse.
# 86 Switch side (or Dome light wire I tapped into. #85 (-) Ground

Now I have two 14 ga. wires running to the bed from the battery and relay area.

Wire #1 runs from the Battery with a 20 amp fuse running to the bed for the dome lamp. Ready for the shell (fuse not in)

Wire #2 runs from the relay #30 Load (lights) running to the dome lamp depending on what kind of light there should be a switch (on/off) connect the wire to the lamp side of the switch.

Thank again
Dogface

 

Dogface,

It sounds like you got it.

If you fuse everything as you wire it, you'll be OK if you make a mistake. You'll just "pop" the fuse.

I also mentioned running a ground (-) wire into the bed because I wasn't sure how well it was grounded to the rest of the truck. If it works without it then no problem.

Good Luck... XLT_D

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XceLenT Driver

I will put a 10 amp fuse on Wire #2 and the bed wiring is grounded.

I have a four wire plug that being used to disconnect the shell from the bed for when I need to remove the shell.

Dome lamp, Brake lamp, Wire #2, (-)Ground.

Thanks Dogface