location of diode box?

[slimcat7m3]

I have been checking out the fsm for an 89 240sx to find a short that I am having and I think it has to do with the wiring somewhere in the area of the diode box and bulb check relay. The fsm tries to show you where the bulb check relay is, but not the diode box that it refers to. I was looking and trying to trace wires and it started getting dark. If anyone knows where the bulb check relay and/or diode box is please let me know. Been looking for this short for weeks. Thanks

[benemorius]

I _think_ it's by the TCU, but I'm actually not sure. Sorry. What exactly is the problem that you're experiencing?

[vancouverbc]

I think this is the diagrm in fsm you were looking at. Its right by fuse box. Diagram makes it look like it is in door.

[slimcat7m3]

Same problem as everyone else, the classic instrument cluster, side marker light, taillight issue, and yes the radio was a piece of crap so I pulled it out. I changed the tcu and that did nothing. All of my side marker lights and taillights have continuity when they are not supposed to. Also I am having something strange happening with my alternator. It seems to be the only area where the instrument cluster lights and alternator are tied together. Not quite sure whats up with the alternator either. It gave me problems, checked voltage of the battery and it checked good, but it wasn't charging with the car running. I had it rebuilt and it wouldn't charge until I revved up the car once I did that it charged fine, eventually it quit charging(2 weeks later) so I took it back to the guy and he rebuilt it again, same thing happened. I found a used alt off an sr20det put it on and it charges like it is supposed to but the alt/battery lights is still on. I am going to pull the battery and have it checked anyway. Also the brake light is on and is also tied to the diode box, not that concerned but maybe it is tied together.

That is the picture in the fsm I was looking at but I don't see a "relay" just like a wire junction box. Like I said I didn't get to look too long tonight it got dark. Thanks for the help.

[benemorius]

Did you clean up and cap off the stereo wiring harness before replacing the tcu? If the tcu was from another car, don't overlook the fact that it could have been bad also.

[slimcat7m3]

I thought about that, I checked the original one and couldn't see any signs of the burn out like I have seen pictured, I will take the cover off of the other on and see if there are any signs of problems. I taped each wire individually so there is no chance they can touch. thanks

[slimcat7m3]

still looking for the diode box

[vancouverbc]

the diode box will likely be very small. look at the wire colours and follow them.

[slimcat7m3]

found the diode box. It looks like a connector hanging down that connects to nothing behind the radio, has a clear plastic around it. One more thing that is not my problem.