so yeah, here's the deal, all dash lights work like on the AC panel, radio, and what have you, but NOT on the cluster... the little LEDs that say if your door is ajar, seat belts not on, and the clock work (clock lights up when lights are off)

i checked all fuses, and relays, all is as it should be... at the shop, we have a theory that the dimmer switch is bad, could this cause it?

just looking for some ideas before i try my 0 mile dual cam cluster in the hole, i REALLY want it to work cause that HUD stuff is kinda cool, and it'd be nice to see my gauges at night...

 

All of the interior lighting is run from the dimmer switch. All the little dash lights in the center should dim with that control. These are the R/Y R/L wires that you see when you do a radio. Run the dimmer up and down and see what happens. If everything works as normal and your clock works, then it looks like something could be wrong with the connectors or harness. The same R/L powers the cluster illumination, and the grounding for the cluster illumination is shared with the clock (which works).

There's also some voodoo that happens in the HUD control unit. It gets a copy of all the dimmer signals. The HUD cluster has it's own brightness control, but I think that's just for the projectors.

-edit- this is on a single cam, and I only have the shitty BootyCDs copy of that. I'll see if i can find a real FSM.

-edit 2- Found the 1989 FSM. Go here: http://www.nicoclub.com/FSM/240sx/1989/

Thanks to NICO for the bandwidth, as well as links to the other FSMs. Thanks to "Mutiny" on NICO for scanning this for everyone!

 

Yeah, that was epic haha. We were all begging him to do it. I offered to do it for him and send it back if he didn't want to do it haha.

I've got a copy of it on my webserver as well. BootCDs too but we don't need it anymore. Actually, a couple of the wiring diagrams were extremely useful.