I was sittin' in the truck waiting for my buddy and I noticed that there is a little square box attached the the back of the rear view mirror mount with wires running into the headliner......What is it???

 

Heck, one of our techs told me it is for the compass.....huh, I guess I should have asked first, oh well peace ya'll

 

Its for either the compass or the automatic lights. My guess would be the lights because i have a compass in my 03 and no auto-lights, and i don't have the box hanging off my mirror.

 

mark03screw,

Notice the MY of the truck he is asking about. '04 + ( non '04 Heritage & L ) moved the compass sensor to just behind / inline with the bottom of the mirror.

In the '04 + the sunload sensor ( autolamps, and part of the EATC HVAC ) is part of the PATS anti theft indicator LED on the top of the dash driver's side ( not under the little grille on the oval as '99 - '03 & '04 Heritage & L ).

 

I'm aware he was talking about an 04', I was just referencing the fact that I have an 03' and 03's don't have autolamps, so therefore I thought it was for the autolamps and not the compass because I do have a compass but no box by the mirror. Thanks for clearing up the question thou cause I wasent sure.


However I do have a question for you. I am currently hooking up a new deck in my truck and it tells me to hook up two wires, one going to the hand brake and one to the foot brake. This is so I can't watch dvds or change the setup while driving. I tried to connect the wires to constant power, but it turns out that you're supposed to use the handbrake, then the footbrake, release the handbrake and then put it on again before the dvd option will work. So obviously it's sending some kind of pulse through the two wires. I was wondering how I could possibly bypass this? Thanks for any help in advance.

 

use a toggle switch that is wired into the hand brake. You can flick the toggle to get the same sequence that you need from the hand brake.

 

mark03screw,

Let me see if I got this correct :
1. Parking brake = on
2. Brake pedal = on ( press and hold until step #3, then release ? )
3. parking brake=off
4. parking brake = on

Don't know if I have the process correct ( check the list, order, and any transitions I have ).

The parking brake switches ground to the ground side of the indicator lamp on the instrument cluster. The power is in the instrument cluster itself, so if this is universal ( that much I do not know ) the parking brake is a ground switch to the HU.
https://www.f150online.com/galleries...028-192225.jpg

The brake pedal is switching power to the tail lamps.
https://www.f150online.com/galleries...028-169795.jpg

If I have the order of operations correct, and the transition for each, then a SPST switch to ground for the simulated parking brake lead
SPST momentary switch to power for the simulated brake pedal.

This would be
1. turn SPST switch on.
2. press and hold the momentary SPST switch until step #3 ( if I got that correct )
3. turn SPST switch off
4. turn SPST switch on

If I got it correct, this would cause the DVD player to work.
Worse case I got the release point for the brake pedal wrong, which means you would hold the momentary SPST switch a bit longer ( until the end of the sequence ? )

Let me know if I understood what you need to have happen to make the DVD player work.