Bare with me as i will try to keep this short. I am a newbie to the site but work in the auto parts/repair industry and have a fair knowledge of vehicle repair and systems.

For a year now i have had the problem with the driver window working when it wants too whether by itself or by switch. Then i had the problem with dome light not shutting off for about 45 mins. after the doors had been opened. However, as of 2 days ago, a day filled with wind and rain, i started my truck, turned on my headlights to find my interior cluster lights and radio panel lights off. The only lights that were on were my signal light indicaters in the cluster both stayed on steady as well as the high beam indicator while the head lights are on low beam, when switched to high beam the hb indicator goes out, signal indicators still on, until switched back to lb at which point the hb indicator comes on steady again. Signal lights do not work during all of this either. Turn the head light switch to off it goes back to just signal and hb indicator staying steadily on. While the headlight switch is off, If i turn the area selector switch for the blower motor to off position the constant signal and HB indicator lights go out at which point the signal lights will work. When the area selector switch is moved to any position( i.e. floor or panel) the indicators come back steady on as well as very dim back lighting for gauges and radio panel and no signal lights again. If i turn the head light switch back on i lose all back lighting again but indicators come back on steady. The only other thing i noticed was if i turn the fan speed switch to position to the 2 highest speeds i get a weird buzzing from near the steering column. The blower motor does not run during all of this. Also i should add that when the headlight switch on, if i turn the dimmer dial to turn on the dome lights they wont turn on unless the switch itself is turned to off.

I am quite positive it is moisture related and quite possibly the GEM, i did pull the dash apart today on my lunch break at work and did see evidence of moisture, mostly surface rust on the metal bracketry behind the plastic. I pulled what plugins i could and hit them with electrical cleaner, the 2 behind the kick panel because there was rust on the body all around it not to mention a hole in the floor board right below them, also the 3 plugins that plugged into the GEM. I cleaned the 2 grounds behind kick panel as well.

My concern is its something else because of the fact that almost all of my symptoms dont line up with other reports. My wipers and washers still work as well as the passenger window works flawlessly. I live in northern ny (near canada northern not albany northern) and our spring so far is still quite moist so it has not had time to dry to see if the symptoms disappear.

I am looking for any info from anyone who might have an idea as to what could cause this. I am probably one of few people praying for it to be the GEM/Fuse box assembly only because i dont want to chase a wiring monster around. Again I am sorry for the length and hope it doesnt deter you from providing input. Thank you in advance.

Should add that it is a '97 F-150 XLT supercab 4.6, 5 speed with 227k miles. Thanks again.

 

Have you checked all the TSB's for your vehicle from the "RECALLS/TSBs" section at the top of the page?

Here's one that might be causing your problem. 98-23-1***GENERIC ELECTRONIC MODULE (GEM) - WATER INTRUSION INTO GEM MODULE - SERVICE TIP

 

Yeah i saw the TSB i just wish it was a recall. I dont want to sink the money into a new one only because im using the truck for maybe two more months then its getting retired.

 

Look for a windshield leak that is allowing water to drip on the GEM.
If your issue only happens in and after rain etc then there is a good chance the GEM is still good when it drys out.
Otherwise is it is a considerable expense as it has to be the specific one your truck uses and has to have the same internal program for 'as built' options.
Good luck.