Air On Board - Fog light switch question

I installed a AOB fog light switch in the blank next to the OEM fog light switch in my 2015 DCLB. Power for the switch is tapped into the tail fuse, the switch is connected to the relay in my aux fuse panel and then to the lights. Ground is connected to the bolt on the fuse box mount. Dash lighting (blue aob wire) is t-tapped to the green wire on the OEM fog light switch.

Lights work as intended and switch lights up when it's pressed. Thee switch DOES NOT light up with the other switches when I turn on the headlights.

I'm thinking that the AOB switch uses a common ground for the dash circuit and the "lit when pressed" circuit. Does that mean I need a diode or is it possible that the tap to the OEM switch is not providing a good connection?

I have another intermittent issue that is more baffling..... On occasion when I turn the lights out my Kenwood head unit loses the Apple Carplay connection and I get an iPod error (caont remember the exact verbiage) but it happens ONLY on occasion when turning off the AOB fog light switch.

I'd like to fix the first issue before tackling the second but if anyone has any ideas I'd love to hear them.

 

may or may not be the same thing man, I’m a novice, but my ARB compressor switch has a diode in each line that I tapped into my fuse box. The light is connected to the 7.5 amp “panel” fuse.

 

If I'm reading this correctly, this switch has 4 terminals/wires. Power, switch to relay, dash lighting and ground.

One of the 2 power switch wires will have continuity with one of the lighting wires.

I assume you have a meter that can check resistance. Using the dash light and ground wires, attach and or swap the leads to get a reading on the meter. When you get a reading, take the positive test lead and probe the switch wires. The wire that gives a reading gets connected to the relay.

 

Correct - switch has 4 wires. Power, switch to relay, dash lighting and ground. Here's a (very) rough diagram of the current set up. The only thing that does not work is the dash light - stays dark when I turn on the lights.
I'm going to check the connection of the tap to the OEM green wire and put a meter on it...

Another point that I forgot to mention. The fog lights do work when the switch is pressed, but only if the parking lights/headlights are on. Something is definitely crossed up....

 

The factory fogs will only work with the headlights on if that is what you are saying by this.

Try running the AOB switch without the spade connected to the OEM fog light tap connected. If the AOB switch still works as intended without the fog light tap and just isn't dash illuminated, that says that is where your issue is.

 

Sorry - my bad..... AOB switch powered lights only work when headlights/parking lights are on

Switch is lower independent that lights up when the switch is on and can be wired to dash lighting.

• Single Pole Single Throw ON - OFF PUSH switch
• Black hard surface rocker.
• Laser etched Legend
• Single upper L.E.D light.
• Single lower L.E.D light.
• Upper light is ON when the switch is pressed IN.
• Lower light can be wired to separate dash light circuit.
• Rated at 3Amp 12V.
• Wiring diagram supplied with switch.

edit - here's the wiring diagram that came with it.... I'm using a different version of #1 where red is wired to the tail light fuse.

 

1. The factory fog switch is only hot with the headlights on, which makes me think that you swapped your 12V inputs to your AOB switch. Double check this to make sure. This would make a lot of sense as the cause.

2. Is the "tail" fuse constant hot or is it only on with the headlights as well? I want to say it was the latter for some reason.

 

That's what I'm thinking too........ I may have swapped the 12v inputs. I'll double check that. If I recall correctly, the tail fuse is always hot when the ignition is on - the headlights did not need to be on. I'm going to recheck that with my meter as well but pretty sure that's what it showed when I tested it before tapping that fuse slot...

 

I'm going off memory on the tail fuse so you're prob right, but never hurts to verify. I've spent SO much time checking fuses with multimeters just making sure of stuff.

I'd bet on swapped inputs from our back and forth but stranger things have happened... If you get super "wrapped around the axle" you could always take the switch out of the dash, put the switch ground wire to the neg post on the battery and the positive post to the dash light wire and bench test it in isolation that way. Who knows, it could just be a bad LED on the board from the factory. Defects happen.

I've learned the hard way (several times...) to test every component in isolation BEFORE you start the install just to verify it is functioning OK.

 

Solved! The tail fuse in my 15 is only hot when the lights are on. I switched to the accy fuse (also 7.5 amp) and it’s hot when the key is on. Fog lights now work without the lights on. The t-tap to the green wire on the oem switch had a bad connection. I cleaned it up and reconnected and now the the aob switch lights up when the headlights are turned on. Everything seems to be in order. I wrapped it up in the driveway just before the rains came and then had to make dinner so I will test more extensively tomorrow to see if the CarPlay issue is still there. So far so good.

Thanks for the help. Sometimes it helps to talk about it out loud and get some feedback on how to break it down.

Also noted about testing before snapping everything in place. Should have known better but will remember next time.

Thanks again!

 

Glad to help!