[NTexasFNG]

2002 1/2 F250 4X4 4 door.
I am trying to figure out what to look for and possible fix. Hope I put this in the right spot.
Interior lights don't come on when door is open. Door open light comes on when all doors are shut. Will not go into 4WD high or low (according to dash lights and no difference when shifted). Truck starts and runs well so far. It does have a Hydra tune installed.
Did Ford change electronics configuration half way into the production year?
Is this an ECM problem?
The truck came with 2 extra modules, 1 used and 1 new. If I install either one of these and the truck will not start and run, can I just put the original back in and expect it to run as well as it does now?
Will this have any effect on the tunes installed now?

 

[DizzyTheDevil]

never install a module that your not 100% positive has been flashed to your vehicle it can create a ton of problems especially when it’s the ecu or the pcm as for your 4x4 problem the 4x4 in our trucks is electronically controlled unless you lock the hubs manually using the hub locks in the center of the front wheels make sure their both in auto position put your truck in neutral turn on 4x4 go back into drive and see if it’s engaged if your 4x4 is not engaging you may have a bad Hub solenoid start with the cheapest solution first test it see if it’s bad hopefully your T-Case isn’t trashed but your lights problem I’ll have to look into and get back to you I’ve heard of it before if the computer has been changed it definitely could play a part these trucks are picky when it comes to aftermarket parts but most of the time it’s installer error

 

[NTexasFNG]

Ha! That worked! Thanks so much. 4X4 does engage when applied as described. I think my next step is to try and find a PDF of owners manual.

 

[Greg687]

Your interior lights and door open problem are likely related to the switch (s) in the doors. There are several threads on how to fix these, but usually just WD-40 will unstick them. Eventually one will break and you will have to replace it.

 

[NTexasFNG]

The seller stated that he had replaced all 4 switches. Maybe I should go through and check each individually.

 

[NTexasFNG]

If it is a switch, wouldn't it make sense that interior dome lights would stay on?
Just check the obvious. Dome light bulbs have been removed..

 

[Greg687]

They did odd things when the switches were sticking on my truck. Wouldn't come on with doors open, then they stayed on when one switch broke completely. Did you say the bulbs are removed?

 

[NTexasFNG]

Yes, bulbs have been removed. Maybe something wired backward?

 

[Greg687]

Or installed incorrectly. What happens when you put a bulb in, does it stay on?

 

[DizzyTheDevil]

Ha! That worked! Thanks so much. 4X4 does engage when applied as described. I think my next step is to try and find a PDF of owners manual.

No worries I completely understand I had some trouble my self when I first got my truck the good news is I think I know your door problem so one of two choices one pull the door switches and spray wd-40 on them one could be not making the connection from being dirty etc plus wd 40 is cheap remember cheapest first and back probe them to test if one has a continuity that doesn’t change from the latch being engaged or disengaged second option buy all new ones and call it a day oh ya one last thing please don’t take this as an insult to your intelligence that is not my intention but I gotta ask because sometimes it’s the simplest solution did you double check to make sure that the dimmer wheel on the dash next to the headlight switch isn’t all the way up because if spin it up until it clicks it will turn on your dome lights