Does anyone know where online I can find a wiring diagram for a 1990 240?? I replaced my factory stereo without a wiring harness and don't have any instrument p[anel lights now. And no, it is not a fuse. Please help!!!!

Wiring diagrams are located here:

http://installdr.com/Harnesses/Nissan-Wiring.pdf

When you installed the stereo you connected your illumination wire to something, which is what's causing your instrument lights not to come on. You have to disconnect the stereo you installed, and leave the illumination wire disconnected and isolated so it won't short the lights out again.

You say it's not a fuse, but it can be. Check your brake light fuse, check your audio fuse. If it's neither of those then move onto your dimmer switch, if it's not that, then most likely it's your TCU (time control unit). You can re-solder the TCU, but you should just pick up another one from the junk yard.

Good luck.

Ok.. I checked all the fuses 3 times and the are all good. Where is the TCU located?

When you're sitting in your drivers seat, it's located by your left foot. The drivers side kick panel, below your fuse box. Open it up and you'll see it. It'll have wires in a harness connected to it. Unscrew it, unplug the wires, replace the TCU, or see if you can repair it yourself.

Good luck.

Thanks for the info. Back to work for me