When I parked my truck yesterday afternoon, I noticed a slight burnt odor. I didn't think much of it at the time - I had just driven 45 miles with no issues.

When I opened the door 6 hours later, I noticed I had no interior lights. Put the key in the ignition and there was no glow plug light on the dash. The truck started and ran fine, so I headed home. Noticed the instrument cluster was dead. The lights on the IC were on, but the gauges were dead.

While driving, I tested the systems I could and found the following not working:

• interior lights
• instrument cluster (gauges and glow plug light)
• radio
• windows (doors and the rear flip-outs)
• driver seat motor
• garage door opener on visor

The other common stuff not listed above (door locks, power mirrors, heater/AC/blower, etc) works fine and I had no issues driving home.

I have not tested all the power points, trailer circuits, other uncommon/rarely used circuits.

This morning I started looking at fuses. Pulled the IC fuse and it blew again immediately upon inserting a new one. Also pulled the drivers seat maxi fuse and replaced it. The seat worked until I put the key in the ignition and turned it to on.

I pulled every other fuse and none appeared blown. The window motor CB appeared to be OK as well.

Intend to pull the fusebox/GEM out this evening or tomorrow morning.

I'm no electrical expert, but the burnt odor and fuse blowing on insertion give me clues where to start looking and what to look for.

Any other suggestions?

 

You have an 02? You don't have a GEM if you do. Ford changed a lot of the electrical distribution up in 02, but the heart of the system is still mostly in the same place:

Under the dash at the central junction box.

That area is still susceptible to water intrusion from the windshield above. Most of the functions that the GEM performed were moved to the instrument cluster in 02. Wires don't "go bad" spontaneously, so there is likely a mitigating factor involved like water, poorly installed after market electronics or rodents.

 

I was reviewing another electrical issues thread and saw that referenced there, hence why I wrote that. I realized mine was different as soon as I dug into it this morning.

As I mentioned in the original post, the only fuses I found blown was #35 for the IC and the maxi fuse for the drivers seat motor. When I put a new fuse for the IC in yesterday it blew immediately. This morning, I pulled the IC out and put a new fuse in - it did not blow. So I pulled the fuse back out, plugged the IC back in, and the fuse blew as soon as it was re-inserted. All this with no key in the ignition.

OK, that narrows things down a bit, but why are my windows and other circuits not working even with no blown fuses? Are they somehow dependent on the IC or is the problem in the fuse box itself?

The wiring behind the fuse box shows no obvious signs of damage.

 

In 00-01 the GEM handled the windows, horn, locks, 4x4 and several other functions. It is likely those have been moved to the IC, but I don't have the 02 wiring diagrams to confirm.

 

Well. A Google search led me to pull the delayed accessory relay in the fuse box and jump pins 30 and 87. This brought the windows to life, but nothing else. Fuse 35 still blew upon insertion.

I also found some wiring diagrams in another forum thread that indicated the IC and the interior & exterior lamps were on the same circuit.

Thinking back to the burning smell - I remembered it was most noticeable near the drivers rear wheel - I went searching and found the rear lamp on the running board had melted, fusing what was left of the light and the socket into a single lump. I cut it off.

Put the relay back in, put a new fuse in #35 and - viola! - interior lights and the IC came back to life. Garage door opener working as well.

Not all is good - I still have no drivers seat motor and no radio, but at least the truck is driveable.

EDIT: I have a very unusual radio and simply had a connection reversed - oops. I think the seat is just a blown fuse.

 

Glad it is working itself out, and you are all the wiser about your vehicle as a bonus.

 

Wish I we're as lucky. I am in the middle of a complete fb tear down. Gem is removed, fused and relays pulled, all clips are out. Will take out the studs and separate all the layers for clean up tomorrow