Screwed around with the charging circuit on the 240 for a while. Thrilled by fixing the hell out of the PV's alternator/charging situation, I thought I'd do something about the 240's weirdness.
The alt light isn't on with the key on, engine off. It should be. And it often acts like no charging is happening, Multimeter confirms it, it's hit or miss. Never a warning light.
It's a 100A small denso from a 940. A few years ago I totally redid the engine harness (part of sequential squirt/COP/DSM CAS/MS3X install) and thought I got the wiring for the alternator correct then.
So I spent a little time trying to verify that the wire down at the alternator, going through my new harness, through my 940 style multiplugs on the engine side of the firewall, and into the car harness inside was all connected to the right places. It seemed to be correct.
Inside the car it's hooked to a large multiplug that leads over to the cluster. I double checked the wiring diagram a time or two, it's the only red wire. But when I ground that wire, the alt light should go on. I tried that, and several other warning lights, but not the alt light, turned on (ABS, Upshift, something else).
I took the cluster out to see if the bulb was burnt out, but it wasn't. Put it back in, no dice. The alternator gets enough juice from whatever is happening on that line to light off *sometimes*, I think it mostly just self-excites (hey-ohhhh). But not always. And once it self excites, it's easier to light off again for a while.
Anyhow, I googled around a little, found some more things to check - I may have some issues on my cluster - Cleanflametrap had some good things to check in this thread:
http://forums.turbobricks.com/showthread.php?t=279601
So I'll take the cluster out again and check for weirdness.