So I've been pouring through this forum for days reading everything to do with the alternator and the associated electrical components, It left me with some questions. I'm having the alternator not charging issue and I can't seem to figure it out. Here's the story leading up to this. I had to deal with an oil pan issue originally which resulted in breaking the body and engine loose from the frame. I disconnected a lot to make this happen, probably more than I needed to. I accomplished my mission and installed a Morosso gasket, since everything was torn down I rebuilt the turbo and installed the AIH delete plug. I removed the AIH ground and 12v lead from solenoid, I left the solenoid in with all of the other wires connected where they were originally. After driving it some it ended up not starting because the batteries had finally gone down. I got it home and found out it wasn't charging. I replaced the alternator and I replaced the solenoid on the passenger side fender and it's still giving me the finger. I did find one loose ground, from the passenger side battery to the body. Fixing that didn't net me any gain either. So here are my questions... I've read in several posts about some fusible links that can affect the alternator. Where are these things? I've been looking everywhere and I can't find anything. Maybe I'm just missing them because I don't know what they look like. I've also read that the AIH relay has some affect on the alternator and could potentially be a problem. How does it affect the alternator? If the AIH relay goes out will that cut power to the alternator and cause it to not charge? Is that linked to the solenoid on the fender in some way? I have power to that solenoid but it won't engage. Lastly, I read that I had to wait two minutes before testing something. I'm assuming that I am waiting for the glow plug cycle to terminate but I'm not sure what I'm supposed to test after that 2 minutes. I've done all of the other things that I managed to find in the past posts, I checked my fuses, checked my grounds, and checked my wires for damage. What am I missing here?

Here are the voltages at all 3 solenoids with the engine running. Sorry for the giant pictures, I couldn't figure out how to resize them,

I appreciate the help, you folks are an awesome source of knowledge. You have bailed me out more than once when I've gotten stuck.

 

I'm thinking that your fender relay is where your problems lie. Mine has two sets of those double wires coming off of it and they need to come off the lug that's hot at all times. What are your readings on that relay with the engine off, key off? Is there another double wire floating around down there somewhere that you missed? And the fuseable links are in that double wire, maybe where they come together and connect to a #10.

 

the fender solenoid is the one I just replaced. I don't remember seeing a second set when I took mine off but I'm damn sure gonna go scour that area and make sure. The readings for that solenoid are exactly the same as when the truck is running. The one post reads constant hot and the rest of them have nothing. Whatever is supposed to power that one isn't, that just makes me think its something further up the line. The other two solenoids had funky readings I thought but I'm just smart enough with electrical to be dangerous.

 

That fender relay is fed directly from the battery, the alternator and (I think) the IAH and the GPR are fed off of one feed and another one feeds the fuse box over on the driver's side. The relay is activated and the cold lug on that relay gets charged when you hit the key and power that little lug on there.

 

 

I'll see if I can get the AIH Relay Switch later today

 

My issue has finally been resolved, Walleye Hunter made the call. There was another double wire that went to the passenger side fender solenoid. Once I found it and put it back where it belongs everything started working like it was supposed to. Thanks again for all of the help.

 

AAahhhhh, that feels good, doesn't it? Congrats on getting 'er done and reporting back.