headlight/highbeams dont work, runninglight/passing-highbeam do work

[bluemeate]

from the research i have done, i take it this is a common problem with the dimmer switch or something?

2000 ford ranger, symptoms
-headlights are out
-highbeams wont switch on, light on cluster wont illuminate
-highbeams will flash on with the lever, light on cluster will illuminate
-running lights work

I checked the fuses, all is fine
then i took apart the front panel and found these wires are corroded but still intact
http://i.imgur.com/7pj5ZRC.jpg

now for my questions
1.how does one use a multimeter (my roommate has one) and how can i use it to make sure the wires work
2. which piece is the dimmer switch? how much are they brand new? should i just go grab one from pick n pull?
3. how much would a shop charge me to fix this?

-also i searched 10 pages back and couldnt find anything with enough info to make things clear so i made this thread,
here are two relevant threads i found
http://www.therangerstation.com/forums/showthread.php?t=125335
http://www.therangerstation.com/forums/showthread.php?t=144141
thank you

 

[bluemeate]

from the website
http://www.justanswer.com/ford/69hk0-ford-ranger-headlight-dimmer-switch-located.html

The dimmer switch is incorporated into the multi-function switch . Start with making sure the #12 fuse in the interior fuse panel isnt blown and if so see if you have battery voltage with the light on at the DB/O wire and the Red/yellow wire at the multi-function switch with the key on and the light on, if so and still no headlamps, suspect the multi-function switch has failed.

not 100% sure what it means but the yellow ones lit up with the bulb tester thingy but the red X ones did not
http://i.imgur.com/KbFiiab.jpg (obnoxiously large image)
i think this means my dimmer is bad?
also #12 fuse is fine

 

[chicagodude]

I ended up replacing the wires and terminals on that switch on the dash. I bought another switch and used part of the plastic connector. The wires that powered the headlights were very corroded. I cut off the old terminals and spliced on new wires with new terminals. After replacing the terminals, I had no more problems with the lights going out.

 

[bluemeate]

so i picked up 3 things from pick n pull
1. (2) headlights
2. dimmer switch
3. non-corroded replacement wire-harness-plug-thingy
I think i will replace them all in that order

 

[bluemeate]

so i picked up a wire harness from a 95 explorer that had 8 wires instead of the 7 that mine had. i matched them all up except for that one extra wire which i just electric tape'd shut.

now i only have one headlight and my blinkers dont work :x

help, please!

 

[bluemeate]

I replaced the 8wire harness with the proper 7wire harness and the right lowbeam still wont work
The blinkers work, high beams work, everything on the dash works
I even replaced the right lightbulb harness and it still wont work, I am going to cry

Help

 

[V8RangerBoy]

Let's backtrack and clarify here.

With the lowbeams on, only the left bulb works? With the high beams on, both bulbs work?