Hey guys,
I've tried to follow some similar threads as to mine but unfortunately have not been able to solve my problem.
For some reason last week my fog lights and high beams stopped working. The fog light indicator lamp does not light up, nor do the fog lights activate when pulling the fog light **** out. Also, the high beams do not activate when pushing the column stalk away from the wheel, however they do come on for the Flash to Pass feature.

I think I have checked all the fuses that would be relevant but none were blown.

I have a '98 scab 4x4 4.6L

Any help would be really appreciated, i've been frustrated for about a week trying to figure out what the problem is. I hope it isn't something really stupid.

Thanks everyone.

 

Did you check them visually, or use a voltmeter or test light?

SL

 

I just checked them visually. I don't have a voltmeter, should I get one? Or just try replacing the fuse? If so..which one?

Thanks,

 

A check of the drawings shows that there would be 3 seperate fuses to fit your condition and all would have to be blown.
However they all go thru the multifunction switch that would be common.
There is a main 30 amp fuse common to all so that one should be ok.
Then there are seperate fuses for left and right hi beams.
The fog lamp relay circuit including the dash indicator lamp. There is a seperate fuse for this that also goes thru the MF switch.
Be sure all the fuses are good. If so that leaves the MF switch the last option.

 

Which fuse # would this be?

Thanks the help!

 

Fuse 27 a 5a powers the Fog relay after the multi function switch.

You can see all this in the Haynes book page 12-24.

 

Ok thanks, I will check that fuse and hope for the best.

 

Considering you have 2 issues, but each one deals with the MFS I would look at it slightly different.

Problem 1. Fog lamps don't work
Problem 2. High beams don't work.

These are assuming that the truck had fog lamps from the factory, and were not added after. --> Can you confirm this ?

P1. Diagnoses steps :
Check Fuse #27 ( as noted above )
* if good :
-Key position not specified ( on / off / assy not important )
-Pull Fuse #27
-turn main head lamp switch to headlamp position, pull out for fog
-Pull back on MFS to ensure headlamps are in the low beam position ( should get a FTP-Flash To Pass indication )
- Use a DC volt meter or test light to check for voltage on both pins in fuse #27 ( should have +12 V on one of the 2 pins for fuse #27 ).

* If no voltage at this fuse position, the MFS is not providing power to fuse #27 -> follow MFS check below

* If voltage at fuse #27 need to check for what could be a burnt out indicator lamp ( for the fog lamps ) in the main headlamp switch
-turn main head lamp switch to headlamp position, pull out for fog
- Pull Fog lamp relay
- Check for 12V DC on pin #1 in the relay socket ( relay pins are numbered on the bottom of the relay, line up to socket for pin assignments ).
* if +12 V DC, problem is with fuse #9 fog lamps or the relay itself.
- Check Fuse #9
* If fuse #9 is good
- Jumper Relay socket pins #3 and #4, fog lamps should illuminate if fuse #9 is good, problem looks to be with the fog lamp relay.

MFS check
Take steering column cover off
Check connector for MFS for bend / malformed / discolored pins.

 

The MFS has 2 circuit sections for the high beams

1. if the FTP - Flash To Pass function
2. High beam section

Fuse #8 30 A has to be good, else the FTP or Low beams would not work ( this is power to the MFS )

check for MFS high beam ( not FTP ) function
-Key position not specified ( on / off / assy not important )
-turn main head lamp switch to headlamp position
- Push MFS forward to activate high beams
- Pull Fuse #16 20 A ( high beam L & R Fuse )
- Check for 12 V DC on either pin of the fuse socket
* If no power > follow MFS check in previous post.

That is what I see with the 2 problems, I see the MFS with a loose connector / bent / worn pins being the source of the problem, considering the 2 symptoms, but this needs to be confirmed with each step

If there appears to be no problem with the connector to the MFS you will need to check the MFS:


Common MFS problems with loose connector, worse discolored pins can come from using the tilt too much, or never for a long time, then start ( from what I have read with others, I have not had this problem, as I set the tilt and leave it until I sell the truck ).

Good luck, let us know what come up with the previous posts, or these test steps.

 

SSCULLY,
Where do you find this stuff? Do you work at a Ford dealer? My friend had the same problem and we just fixxed it thanks to your post!

 

I work at a telecom equipment mfgr.
I just look at the diagrams, and put together trouble shooting ideas.
Not that much different then work, but it is 12V rather then A-bis interfaces

One thing, please do share what you guys found to be the problem with yours, in trying to help t-wash. Sure he would appreciate the pointers.

 

While no one asked, I will offer that I also have more than 50 years of chasing and trouble shooting in the telephone and electronics field and have a limited automotive library to work from plus factory service discs and as many years of automotive work to go along with it.

 

The problem was the cracked wires in the MFS. I can only assume it was like that from being in one spot like you said for 10 years (97 f-150, no tilt column) Thanks again

 

Good for you.
There is aways an answer if it once worked, then not.
The time when problems become a bit more difficult is when someone has futzed with the wiring and we can't catch up with it by normal circuit analysis and it depends on the person doing the work to see it or know about it..

 

Hey guys,
Thanks for all your detailed instructions. I am going to work on this tomorrow and will definitely post what I found the problem to be.

Thanks again,