Well just hopped in the truck, flicked on the lights and nothing! My fog lights work but nothing else.. Any solutions?

Also there is a female adapter by my left foot that says LF on it, its not plugged into anything?? I just find it wierd b/c it just happened..

 

Is there a process of elimination to go through.. Switch, relay or fuse? Figured someone with a similar problem would chime in, I can't be the only one..lol..

 

Some additional questions :

1. Do you have parking lamps ?

2. Are you using Autolamps, or the park - head section of the switch ?

3. Did you move your ground on your fog lamp relay ? ( so they stay on with the high beams ).

4. If you use the FTP ( Flash To Pass ) do the high beams work ?

5. Do you use your tilt on your steering wheel column ?

6. Do you turn signals still work ?

7. Do your brake lamps ( all 3 ) still work ?

8. Have you do any work as of late under the dash ?

9. The connector that is by your left foot ( by the parking brake foot lever ) what color is it, and how many pins are in it ?

 

1.yes
2.autolamp didn't work the other day either, didn't think much of it..
3.didn't touch anything.
4.nope, pull the brights in nothing.
5.tilt is the same since i bought it.
6.turn signals are fine.
7.yup.
8.no work done, just bought the truck bout 3wks ago.
9.connector is black with one pin (female), something you'd plug a cellphone in to recharge it. It has LF on the back of the plug? no clue what thats for.

Also when I hit my keyless remote open doors, all other lights come on except the head lamps, they used to..well yesterday they did..lol

 

Additional question, and then some problem diagnoses steps
10. Do you have the Daytime Running Lamp ( DRL ) option ?

With your fog lamp relay still finding the high beam element for ground, that means the wiring ( to at least the high beam) is good.

Considering this is all lights ( lo / hi / FTP ) did you replace fuse F40-20 A ?

Fuse F40 feeds the main headlamp switch, and the FTP function in the MFS. Without this fuse there is no output of the main headlamp switch to the MFS for beam selection, and the bypass of F40 to the MFS for FTP would be dead as well ( on the surface, the problem you are seeing ).

If you want to check the operation of Fuse F40:

1. Pull fuses F23 & F25 ( 10 A each )
2. Turn the main headlamp switch to the headlamp position
3. Pull back on the MFS ( to make sure the low beams are on )
4. Place one side of a meter in the fuse socket for F23 & F25, to find +12 V on one pin on each fuse slot ( other side of meter to ground, there is ground lug to the lower right corner of the fuse panel )

If you do not have power on at least one pin in each fuse slot ( F23&F25 ) then fuse F40 is blown or the main headlamp switch is bad.

Fuse F40 should be hot at all times, and you can meter this fuse holder as well for voltage on one of the two pins, as noted above for F23 & F25.

If you have power on one side of fuse slot for F40, and repalced the fuse with a known good fuse, next is to check the main headlamp switch for power to it.

Fuse F40 is fed to the main headlamp switch via the Dark Blue w/ Orange stripe wire, circuit 196. At the main headlamp switch connector, this is pin 6.

Check the above items, and let us know what the results are.

Good luck

 

Uhm, as far as daytime running lamps, when i start my truck no lamps come on, they used to i believe. Also, when i turn my dial to autolights, and its dark out, my dash lights still don't come on, but when i turn the dial to my reg lights, the dash lights will come on.. I'm gonna check the fuse tomorrow seeing everytime i get home from work its dark out. Thanks a ton Scully, much appreciated.. i'll keep ya posted.

 

That could be autolamps, were the tail lights also on at that time ?> Teh DRLs are only the headlamps, and they are on at a lower wattage ( DRL resistor inline ). If you look under the hood, there is an AUX fuse panel, that would have the DRL enable relay in it. That is the quick way if you do not recall if the tail lamps were on with the headlamps ( autolamp function )

That would make sense.
Power from Fuse F40 is needed to make the Autolamps work. Without power from Fuse F40, the parking lamps are not turned on.

You are going to need a flashlight one way or the other. The way the fuse panel is, you are not going to see what you are working on without one.
Take your flashlight and a 20A fuse out to the truck, and replace Fuse F40, and I think your problems will be gone.

Good luck

 

This F40 fuse, is this in the fuse box inside the truck or under the hood? When I turn my switch all the way to the right and pull out, my amber lights come on and my fog lights. Everything on my MFS work fine (wipers, spray, blinkers)*Except my brights and FTP. I'm really hoping this fuse is the root, I've only had the truck since Xmas, and its a killer not being able to drive it at night.. Thanks,

PS.I'd love to try that now but its 9pm and -29deg outside..lol

 

I'm going to be the odd man out here, have you checked the bulbs to see if they burnt out?

 

Funny, I just got done reading the thread and I was thinking the same thing. As I understand it, neither headlight works on either bright or dim. I have seen threads on forums like this where either the brights or the dims wouldn't work and it turned out both bulbs were burned out on one beam. Well definitely SOMETHING TO KEEP IN MIND.

 

Yeah, someone else asked me that also. I did take off the light and remove the bulb and it did look like the 2nd element (brights) were burnt out.. I'm gonna try this fuse first then move on to the lights. But if it was my lights, shouldn't the light on my speedo cluster light up telling me I have my Brights on? Or even the FTP light on my cluster.. I'm going out now to try the fuse..

 

Scully, I owe you a ton man! F40 was pulled and it was blown, put in another 20a fuse and it now works! Thanks for your quick and detailed response, I'm new to this site and I love it already..lol..

John

 

As far as that lil adapter, I think the person may have had a Sirius or XM radio hooked up on the dash? Or even a small GPS b/c there is a slight circle image on the corner dash. I'm not to worried about that though, more less interested. Thanks again,

 

johnny1313,

Glad it was an easy fix, and I guess -29 could be a good reason not to do it last night
I feel like such a girl now, it is -4 to -10 over night here the past week, and I don't like messing around in that.

The question on the bulbs, knew at least one of your high beam elements worked, as that is where the fog lamp relay gets ground from. When power is applied to the high beams, the coil on the fog lamp relay has power on both sides, and opens the contacts.
That is one to keep in mind, if your fog lamps don't work, start with do your high beams work. That has gotten more then one person, and I went more rounds on a thread for that issue with another member myself.

 

I have no low beams (L/R) also, High beams and fog lights work. I'm in the process of trouble shooting the fuses/lookin at the bulb itself