Gen 2 Light not lighting upon startup

[n8roro]

Hi all and I hope you are having an enjoyable Thanksgiving weekend. The weather here is warm for this time of year so its nice to get out and work on the truck.

I read through what I could find on various gen 2 posts here, but I have not found the solution to my problem of the gen 2 light never coming on. The truck seems to function fine except for this issue, and here is what I have done so far:

-Gen 2 bulb behind the dash is replaced with a confirmed good one.
-All fuses are good in the cab are good
-fusible links were inspected and seem fine.
-New relay installed
-Both alternators are charging both batteries.
-Replaced the belt on the passenger side alternator (Gen 2)
-Voltage gauge was shot and has been replaced and voltage goes from around 24V while glow plugs heat up on startup to around 28-29V when running.

Notes/questions:

The truck starts and runs fine, but it bothers me that the light is not functional.

The gen 1 alternator looks new, but the gen 2 looks original.

Do you think an alternator rebuild required to address this?

Could the diode before the relay be the issue?

My next steps:

Trace the orange wire from the fuse box to the instrument panel, and trace the wires form the relay to the bulb to check for broken wire.
Put a multi meter on the relay leads as well as the light bulb socket contacts.
Find the diode and test it as well.

Let me know if any of my next steps are a waste of time. I am running out of ideas and feeling like I am chasing my tail a bit. Any help is appreciated.

Thanks,

Nate

 

[n8roro]

Gen 2 light magically started working last night and worked today as well! The only thing I can think is it must have been a loose connection somewhere. I never found any broken wires and the alternator was charging as it should. I'm just happy it works.

 

[sneekyeye]

If it happens again, I would suggest a new bulb socket. Oxidation over the years can create a poor contact inside the socket itself. You could clean it if you wanted and had a piece of fine sandpaper.

 

[n8roro]

I looked into the socket first by cleaning it, swapping bulbs, and swapping gen 1 and 2 sockets. Only gen 1 would ever light for me. Traced wires with no sign of fraying or broken wires, and all fusible links and fuses are good. A couple months ago I sprayed corrosion x on the electrical connections under the hood and used dielectric grease on the alternator plug. Maybe that helped over time? Funny thing is I bought new sockets a few weeks ago because I was running out of things to try, but have not had a chance to install them yet. I'm relieved it works, but it's not very satisfying that it repaired itself. Hope it stays that way, but I'm not holding my breath.