Wiring a rear fog lamp
- Thread starter doktormane
- Start date
I would use a relay. Feed the switch trigger line on the relay with current from your fog light positive feed. That way you’re not adding any load to your fog light wiring. If you want, run that trigger line to a switch on the dash so that if you don’t want the rear lights on with the fogs, you have a choice then.
I’ve done this same thing with the LED’s I’ve put on the rear bumper, but they are triggered by my reverse light and I can manually trigger them with a switch on the dash.
I’ve done this same thing with the LED’s I’ve put on the rear bumper, but they are triggered by my reverse light and I can manually trigger them with a switch on the dash.
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Why would you want to wire a rear light into the front fog lights? While a relay is always the best way to power aftermarket lights, I would think any rear facing lights would be wired into the OEM back-up lights. I am in the process of adding brighter back-up lights to mine. I have a relay under the hood, a dash switch powered from the backup light circuit (tapped in at the drivers side kick panel).
Thanks for replying!
Well, I want it to turn on at the press of a button, ideally the fog lamp button. I don't think wiring it to the back-up lights would be a good idea.
Yes.
The fog light won't be on, unless you put the gear on reverse which is not right.
If you need to install a button or add a new connection, use a relay.
Jim King
TJ Enthusiast
I replaced my back up bulbs with LED but it made a marginal difference. Anyone have good luck with an upgrade? Or should I just mount a fog light back there?
The Quadratec LED Tail Light Kit for 98-00 Jeep Wrangler TJ,
https://www.quadratec.com/products/55213_0114.htm
is a kit containing complete rear light housings with LEDs, and includes the right LED flasher module and electrical connectors for plug and play installation. More importantly, they are very bright. The backup LEDs are brilliant, you won't need supplemental lamps, and the brake lights are also much brighter than stock ones. The LEDs reduce power draw significantly, so you could splice in some additional LEDs if you want without running wiring from the battery. I have a small 'rock light' mounted on the lower edge of my OEM rear license holder, for easier backing down my long dark driveway.
Use an LED rear fog and it'll be fine wired into the fronts. They don't add enough current to matter. It'll keep the wiring simple. You could just put a single high power rear LED running light instead.
Thanks for the tip. I need it to pass the yearly inspection and as mine is an import and it didn't come with a rear fog lamp I need to wire it myself. Fun fact: A rear foglamp was standard in many EU spec tj. There are mounting holes on the rear bumper.
Okay so quick update. I found out that there is a plug for the rear fog lamp in the dash (at least that's what I think it is) but there is no wiring going to the back of the vehicle. Because it is a non US feature only, I didn't have much luck finding a wiring diagram online. Could somebody help me out with this? Where do I hook it up? How do I trace the plug in the dash to make sure it is the right one?
Question: the factory rear fog lamp has 4 wires. One is for ground, one is for on and off, one is for the accessory light but what is the fourth wire for?
May be like the factory front fog lights where they can only illuminate if/when the headlights are also on?
Well strangely enough in some service manuals it shows the rear fog lamp connected to the front fog lamp switch but I know that in the UK the rear fog lamp had its own separate switch, next to the wiper and rear defroster switch.
Here's how I wired my rear LED light. I like the idea of accessories having their own independent circuit. The fuse tap goes into an existing fuse space or a spare with power. The original fuse for the accessory is retained and a mini fuse protects the light(s). Wired as shown the mini fuse will blow if there is a short, etc. in the light circuit while the accessory is still protected with it's own fuse.
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