Bizzare....non Valk

[Rio Wil]

I had a overhead map lamp go out in my 2006 F150 Lariat pick-up. Simple enough fix....pull the lamp assy out of the overhead liner and change the bulb. Did so and all was fine for a couple days. Then the electric locks, electric sun roof, electric sliding back window failed and the entire dash panel went dark. OkKkkkkk,  a blown fuse.......checked fuses after browsing internet and found f21 blown, which supplies the dash lighting.  Replaced and oddly enough the windows, locks, etc worked also.   Ok....alll good. Couple of days later, same symptoms, locks, windows and dash out.  Shoulda left the blank blank map light out!!!!.
So, thinking back to the last thing I did, ( which was replace the map lamps) I left the map assembly disconnected from the power and the connectors off the switches for the sun roof and rear window.  Good after three days or so, so gotta be in the switch-lamp assembly......
The circuit traces on the lamp assy are nice thick copper/brass etches suspended off the plastic by little white standoffs......looks good enough, but gotta be something amiss here to make it blow fuses.  When putting the lamps back in to their twist in socket, I noticed the driver side lamp holder was a bit loose when turned into place.  Also noticed that the circuit trace near the lamp connection point was a bit dis-colored.........and it had broke free from the little white stand tab and was ever so gently touching another trace........  Guessing that the loose lamp connection heated up the circuit trace which melted the little white plastic stand-off allowing the heated trace to contact its neighbor and blow F21 15A. Why does a blown map lite fuse take out the dash, locks, windows, sun roof, back slider.....only the Ford engineers know ......

I saw references on the internet to "after replacing the map lamps, my windows, dash lites, etc don't work......thought they were crazy.....


Oops.......made a boo-boo, the door locks worked

[da prez]

  Modern technology. Not an item for the apocalypse . I have seen (?) simple technology built from store bought items dis-able a computer controlled vehicle.
  I quit trying to learn in my later years as a diesel / heavy truck mechanic. Way to complicated for my brain. When computers went in the heavy vehicles , Tow trucks were needed as we could no longer bypass the system to limp the trucks in.

                                                                 da prez

[cookiedough]

glad you got it figured out.  I would've been without the lamp probably not trying to figure it out.  It is usually something simple, but to find it is very hard.

Past 3 years or so my dome light switch does not work right when open the doors so I shut it to OFF all the time can live without it.  ONLY time I dislike is in the dark but if I need the light I can turn it ON all the time just gotta switch it back to OFF when done.    Something inside the unit that has ON/OFF/AUTO when doors open then goes out after 20 seconds or so which is the part that does not work.  I tried replacing a marker light in back of the car not really needed is not the brake light, but other light below it, and can see it but cannot get my hand in the opening and do not have a VERY long thin pliers to get in there to remove it so skipped it the past 2 years or so.

[h13man]

I changed out the the 3rd eye brake light on our inherited 07' Ridgeline. The OEM had incandescent bulbs thus it was completely melted down and of course spending 8 yrs. in the Florida and Houston sun probably didn't help. The new one is LED. Basically the OEM was the usual white plastic variant used in vehicle applications.