flipture

First I'd like to say hello to everyone since this is my first post on here. I just picked up a 93 240SX SE a few days ago. I've wanted one for quite some time now and finally have it!!! :-D

It had a couple of problems when I bought it, one being the gauge cluster does not light up behind the speedo and tach and also all of the a/c, heat, and other switches, when the head lights are turned on. The previous owner said that he was installing the head unit and shorted something which blew a couple of fuses. He replaced all of the fuses that were blown and everything that went out came back except for the tach/speedo lights.

I've done a lot of reading and research over the past couple of days so I'm not just asking this question blindly. I've got it sorta narrowed down but don't really know where to go from here.

Here is what I've checked/done so far:
1) Read the factory service manual
2) Checked fuses (i'm pretty sure the fuse that this runs off of is the second to bottom left, i found that it controls the rest of the lights in the cluster like the low fuel light etc...). Fuses are fine.
3) Pulled out the gauge cluster and checked bulbs. The bulbs look fine and it shouldn't be the cluster anyway since the heat and a/c lights dont work either...
4) Checked the connections behind the head unit. Everything looks fine so i don't think he accidentally grounded something wrong back there. I even unplugged it completely and tested to see if he had something funny going on. Still no luck.
5) Pulled out the dimmer switch, inspected, and tried to bypass it by bridging the two wires on to make it light up (dont' remember which wires it was exactly but i read a thread on here that pointed out which 2 wires it was...). No luck

Where should I look next?? I'm stumped! I have my volt meeter ready...

 

rogoman

Possible problem with the light switch.

flipture

I checked the switch... Pulled it out and bridged the two wires without the switch on to see if it would cut the lights on but didn't. I think thats ruled out...

rogoman

There's the light switch on the steering column and a dimmer control on the left side of the steering column on the dash. You mentioned the dimmer in your post, so which one did you check.

If you checked the dimmer being OK, then check the light switch.

flipture

Are you talking about the light switch as in the one that turns the head lights on? or is there another one? The head lights turn on when i flip the light switch so i'm assuming that is not the problem...

 

flipture

Update...

Checked the bulb in the dimmer switch and it was blown, so i bridged it there so it wouldn't kill the whole circut. Still no luck. I went ahead and grounded teh head unit to the chasis instead of the ground in the harness (which turns out to be attached to nothing) like someone else said.

I still have 2 extra wires back there, illumination and dimmer that aren't in use... Are those required to be hooked up to make anything work? I'm assuming not since it looks like they run paralell...

flipture

Ok, i found one more thing to try. for anyone that is interested, this might solve your problem:

http://forums.********.com/zerothread/158162

I'll report back on how it works...

flipture

Turns out i didn't see any visible damage to the white box.. I wana try to get one that i knwo is good to test with but doing that didn't help. Also where it says to ground that one wire at the end, it just kept blowing a fuse...

Any more suggestions?

flipture

Found a bulb or two in the back of the cluster that were burned out and replaced them but that didn't help. I did find that i do have power running through the lights on the back as far as i could test... I guess that means a grounding problem somewhere?

keep in mind that the guy that i bought the car from said this all happened when he was installing the head unit and touched a wire to something that shouldn't be touched to...