Sponsored

Factory Fog lights quit working

OP
OP
Hibypass

Hibypass

Well-Known Member
First Name
David
Joined
Jul 25, 2018
Threads
13
Messages
143
Reaction score
180
Location
Houston, TX
Vehicle(s)
2018 JLUS
Vehicle Showcase
1
So - did you ever discover the root cause? Mine stopped working sometime in the past month. I've disconnected and removed my front bumper a few times doing various modifications but the connector is solidly plugged together and I can't see any issues with the wires. I also checked all the fuses (F26 and F29 per suggestions from another post) and everything checks out. Is there a relay that maybe went bad? Anyone know which one to check because nowhere in the manual or CB Diagrams does it mention "Fog Lights". I haven't put 12V directly to the fog light wires yet but that is my next step to rule out the lights themselves or wiring from the connector to the lights. I'm thinking it has something to do with the switch on the lights dial itself, or maybe it is getting a false high beam signal somewhere. I searched the system pages and couldn't find anything in there to check or adjust so not sure where to start looking next.
Went to different dealer. They said wires were pinched and replaced the wiring harness. They said they didn’t see any tape job. When the bumper was removed, Evidently the wires got pinched between the frame and bumper shorting them out. Costly mistake...:headbang:
Sponsored

 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
Went to different dealer. They said wires were pinched and replaced the wiring harness. They said they didn’t see any tape job. When the bumper was removed, Evidently the wires got pinched between the frame and bumper shorting them out. Costly mistake...:headbang:
That helps. Though I don't think that is the case in my situation a quick continuity check and attempting to turn them on with a separate 12V source will answer that question. I have had the bumper off several times though so if the wires are fragile I may have pinched them at some point and broke them. In that case I'll replace with my own wiring....

Thanks!
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
Well, continuity checks on all the wires on the bumper side of the harness (from the main connector to the ends of the two leads going to the lights) were good, so I don't have any broken wires in the harness on the bumper. My old multimeter doesn't have a diode test mode so I can't check the LED lights themselves - I'll have to wait until I have some longer leads to run power straight from the batter to the lights to see if they illuminate.
 

Kenny

Well-Known Member
First Name
Ken
Joined
May 31, 2018
Threads
82
Messages
1,472
Reaction score
1,915
Location
Utah
Vehicle(s)
2018 jl sports, 2015 JK Unlimited, 2013 JK @ Dr
Occupation
Village Idiot
Clubs
 
Well, continuity checks on all the wires on the bumper side of the harness (from the main connector to the ends of the two leads going to the lights) were good, so I don't have any broken wires in the harness on the bumper. My old multimeter doesn't have a diode test mode so I can't check the LED lights themselves - I'll have to wait until I have some longer leads to run power straight from the batter to the lights to see if they illuminate.
I had the same issue. I got a steel bumper and the foglights worked great and then one day they stopped. Both at once which was surprising. I took it to the dealer and showed them. They walked over, his the middle on the light knob and they came on. I looked like a frickin' idiot, but was happy. Just saying, you might want to check that. I am sure you did - but just saying.....
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
I had the same issue. I got a steel bumper and the foglights worked great and then one day they stopped. Both at once which was surprising. I took it to the dealer and showed them. They walked over, his the middle on the light knob and they came on. I looked like a frickin' idiot, but was happy. Just saying, you might want to check that. I am sure you did - but just saying.....
Thanks - sometimes it is the obvious stuff, but not in this case... Pressing the light dial switch is definitely not activating the fog lights. I've even tried it in different modes (AUTO, ON, Parking Lights) and nothing. The switch does have a tactile feel like it is activating, but the lights don't come on and I don't get the fog light indicator on my instrument cluster either.
 

Sponsored

Kenny

Well-Known Member
First Name
Ken
Joined
May 31, 2018
Threads
82
Messages
1,472
Reaction score
1,915
Location
Utah
Vehicle(s)
2018 jl sports, 2015 JK Unlimited, 2013 JK @ Dr
Occupation
Village Idiot
Clubs
 
Thanks - sometimes it is the obvious stuff, but not in this case... Pressing the light dial switch is definitely not activating the fog lights. I've even tried it in different modes (AUTO, ON, Parking Lights) and nothing. The switch does have a tactile feel like it is activating, but the lights don't come on and I don't get the fog light indicator on my instrument cluster either.
I really felt stupid posting it might be the switch. You ran the continuity check - did you happen to just apply power to the bulbs? I hate to admit this, but when the lights didn't come on and I hadn't been to the dealer I picked up a set of OEM LED fogs. If it's the lights I can help you out
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
I really felt stupid posting it might be the switch. You ran the continuity check - did you happen to just apply power to the bulbs? I hate to admit this, but when the lights didn't come on and I hadn't been to the dealer I picked up a set of OEM LED fogs. If it's the lights I can help you out
Haven't done that yet - that's my next step, followed by tying in a different set of lights to the switch to see if it's the switch or the lights.
I tried to do a continuity check on the LEDs, but they don't work like incandescent bulbs for Ohm checks and I don't have a Diode Check mode on my older multi-meter. I need to get some leads with alligator clips...
 

Kenny

Well-Known Member
First Name
Ken
Joined
May 31, 2018
Threads
82
Messages
1,472
Reaction score
1,915
Location
Utah
Vehicle(s)
2018 jl sports, 2015 JK Unlimited, 2013 JK @ Dr
Occupation
Village Idiot
Clubs
 
I. Have no problem sending my extra set and you could plug them in and see if they work if you don’t want to deal with a dealership
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
I. Have no problem sending my extra set and you could plug them in and see if they work if you don’t want to deal with a dealership
I very much appreciate the offer, and will keep it in mind if my checks identify the lights to be the issue. My helper (daughter) will be home from college this weekend so I should be able to get the checks done then - hard to reach all the things you need to when you are one person! I'll update with what I find - and hopefully will figure it out before the weekend is over! It's driving me nuts.

View attachment 291644
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
So I made some leads and powered the fog lights direct off the battery to the terminal block on the bumper wiring harness... lights worked perfectly.
Tested continuity from the ground on the chassis side of the wiring harness and it was good. So at that point I know either both hot wires on the chassis side are broken, a circuit breaker that I haven't discovered yet is blown, or the foglight switch on the light switch is bad. Turned on the jeep, turned on the lights, pressed the fog light button (center of the light switch), and everything worked... WTF? Turned them off, then had a hard time getting them back on again but eventually they turned back on after a couple presses. So it appears I have an intermittent switch issue - which of course sucks. It will probably always work now except when I really want them to. All the electronics was the one thing I was concerned about purchasing the new JL model over athe tried and true JK model. I hope this is as bad as it gets.
 

Sponsored

Kenny

Well-Known Member
First Name
Ken
Joined
May 31, 2018
Threads
82
Messages
1,472
Reaction score
1,915
Location
Utah
Vehicle(s)
2018 jl sports, 2015 JK Unlimited, 2013 JK @ Dr
Occupation
Village Idiot
Clubs
 
So I made some leads and powered the fog lights direct off the battery to the terminal block on the bumper wiring harness... lights worked perfectly.
Tested continuity from the ground on the chassis side of the wiring harness and it was good. So at that point I know either both hot wires on the chassis side are broken, a circuit breaker that I haven't discovered yet is blown, or the foglight switch on the light switch is bad. Turned on the jeep, turned on the lights, pressed the fog light button (center of the light switch), and everything worked... WTF? Turned them off, then had a hard time getting them back on again but eventually they turned back on after a couple presses. So it appears I have an intermittent switch issue - which of course sucks. It will probably always work now except when I really want them to. All the electronics was the one thing I was concerned about purchasing the new JL model over athe tried and true JK model. I hope this is as bad as it gets.
But you were able to troubleshoot all the way - that's what a REAL man does - none of the dealership BS. Good job
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
But you were able to troubleshoot all the way - that's what a REAL man does - none of the dealership BS. Good job
So now they are on all the time when the lights are on. When I hit my high beams this morning, the fog light icon remained on which was odd, I thought it went off before indicating the fog lights were off (which they should be when high beams are activated). I didn't have time to get out and actually look (will do that tonight).
I'm thinking these things are routed somehow through the ESC/Brains of the vehicle and maybe my jeep has contracted Corona Virus... LoL Or maybe I just need a Corona.
I have downloaded a UConnect Update and will get that loaded this weekend as well - maybe that will fix things.
 

Kenny

Well-Known Member
First Name
Ken
Joined
May 31, 2018
Threads
82
Messages
1,472
Reaction score
1,915
Location
Utah
Vehicle(s)
2018 jl sports, 2015 JK Unlimited, 2013 JK @ Dr
Occupation
Village Idiot
Clubs
 
So now they are on all the time when the lights are on. When I hit my high beams this morning, the fog light icon remained on which was odd, I thought it went off before indicating the fog lights were off (which they should be when high beams are activated). I didn't have time to get out and actually look (will do that tonight).
I'm thinking these things are routed somehow through the ESC/Brains of the vehicle and maybe my jeep has contracted Corona Virus... LoL Or maybe I just need a Corona.
I have downloaded a UConnect Update and will get that loaded this weekend as well - maybe that will fix things.
All that is interesting. I would like to have the fogs stay on when the brights come on but you need to buy a prorammer to do that. I work with Europe people so I go to work/gym at 4:00 so I have the road to myself so I use the roof LEDs instead of brights. That way the fogs stay on and light the close are better. Where do you find the Uconnect update?
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
All that is interesting. I would like to have the fogs stay on when the brights come on but you need to buy a prorammer to do that. I work with Europe people so I go to work/gym at 4:00 so I have the road to myself so I use the roof LEDs instead of brights. That way the fogs stay on and light the close are better. Where do you find the Uconnect update?
Best to just Google Search UConnect Update - there are a ton of videos on it. Once on teh UConnect website you basically type in your VIN and it tells you if there is a new update available for your vehicle.
 

me109stock

Well-Known Member
First Name
Martin
Joined
Sep 10, 2019
Threads
1
Messages
197
Reaction score
243
Location
Linden, CA
Vehicle(s)
2018 JLU Rubicon 6-Speed Manual; 2008 Ford F450; 2003 Porsche Boxster S
Vehicle Showcase
1
UPDATE... Getting into the Jeep Saturday afternoon after shopping, paying too much attention to the people in the car next to my Jeep, I swung my knee up and slammed it into the light control pushing the entire assembly into the dash. I tried to pull it out and ripped off the outer ring of the knob. After a few choice words directed at myself and my own stupidity, I got home and tore the dash apart to re-seat everything properly. PITA. BUT - after disconnecting the switch from the terminal connection, fixing everything, and plugging it back in - MY FOG LIGHTS WORK PROPERLY AND TURN ON AND OFF NOW!

I'll sum all this up to just more loose connector issues from the Jeep factory. I'm just glad it's fixed.

:)
Sponsored

 
 



Top