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I have a 2000 7.3 PSD F350 (rust free) i picked up out of NM last summer. Unfortunately, the PSD gave up the ghost and developed what appeared to be a crack in one of the cylinders. I had a 2002 F350 PSD I had owned and cared for since its birth but unfortunately, had lots of body/frame rust (thus the reason for a rust free one). I had the engine swapped over into the 2000. Everything was fine for several weeks, then this week I had the engine lose power and shut off a couple of times. I could immediately re-start it. Thought it was the cam position sensor. Replaced that last night and taking a test drive, I noticed the headlights flickering, then everything went dark and idiot lights on dash began flashing on/off and with engine dying. I think I also saw the "overdrive off" light flash as well. Fast forward to today, I start to look over fuses and whatever I could on electrical system. When I would turn the key on, the dash electronics would flash on/off 3-4 times then stop and everything was dead. Could not start it. If I let it set for a few minutes it would repeat the dashboard lights going on/off with turning the key to run position but with fewer times of clicking on/off. Now it won't even do that. Now for even weirder stuff. After one of these on/off episodes, I had the key in off position, I went to the engine compartment to check a few things. As I returned to the cab, I hear a noise from left side of dashboard that sounded like a little plastic motor running rough (key in off position). Turning the key on/off did not change anything. If I turned the light switch to on for parking or headlights it would stop. As soon as I turn light switch to off, it would start again.
Where do I start? I checked the wiring harness from gear shift lever and it is OK. All fuses are OK, but have not checked relays.
Kinda sounds like a GEM ghost. It's the module behind/attached to the interior fuse panel. It controls pretty much everything in the cab, windows, locks, gauges I believe. They can get water damage from a windshield leak and go kind of crazy. I've even read of people having their trucks fire up by themselves.
That is part of my plan. Mechanic friend suggested removing bolt and connector and to look down into it with a mirror for corrosion. Had it happen on our Excursion. Made sizzling/crackling noises. Mechanic friend said they are not always available as replacement parts??
Headlight should work even if the other stuff doesn't it almost sounds like you have dead batteries which can cause all kinds of crazy things. Check your batteries and if they're not Dead start checking your ground connections you may be losing a ground.
So far you've been given three good places to start. The GEM can be opened up and restored but it's a tedious job, there is a fantastic write up on it here should you have to go that route. Bad grounds can drive you nuts too so you can toss that onto the pile of things to look into, particularly since you swapped the engine. There are two main ones on the front of the engine behind and below each battery. I always clean and grease such connections when I have them apart. Then there are a few other, smaller grounds scattered around but I don't know where they all are.
Edit: found it in the 7. 3 Tech folder which can be found at the top of the forum page. There is tons of great information about our vehicles in the tech folder . In that thread there is also a link to rebuilding the GEM.
To reiterate with the headlights acting up i don't think this is a GEM issue. Was trying to find headlight wiring diagram to prove that it doesn't go through the GEM but I'm on my phone and I'm having no luck. I won't be back to my computer till I get through turkey hunting and that may be a few days Maybe somebody else can pull up the headlight wiring diagram. I think it goes from Power to the headlight switch to the multifunction switch on the column to the headlights. If this is the case that would indicate a full system power issue not a GEM issue.
Ford dramatically changed the wiring in the 2002 and up models, as distinct from the 1999-2001 models.
Since you installed a 2002 engine in a 2000 chassis, keep in mind that there are wiring differences between the 2000 and the 2002 as you pursue circuit diagnostics and repairs.
OK, guys. I was looking for some more GEM info and found this video on YouTube. At 4:00 in the video he captures the sound I previously described as a plastic motor making noise but he is describing it as a fat cricket chirping. In my case it starts slow with a couple of chirps and then it speeds up until it is almost constant and stops when I turn on the headlights or parking light switch, though neither set of lights are working at this time I have not finished his video yet but assuming his diagnosis was correct on his truck, sure seems likely??
It is now where all electronics are dead. No power to anything I can detect. Was in the process of checking grounds on the batteries when I found this video. Let me know if you agree or think it is something else
Maybe somebody else can pull up the headlight wiring diagram. I think it goes from Power to the headlight switch to the multifunction switch on the column to the headlights. If this is the case that would indicate a full system power issue not a GEM issue.
