Did you try disconnecting the dimmer and wiring the in and out wires together? Do you have a tow harness?

 

if you have a tachometer gauge you also have a solid state dimmer controlled by a potentiometer not a rheostat..

 

I havent tried that yet, I'm gonna tear into it this weekend. Is there a way to access the dimmer switch or its wiring from popping it out of the dash? Or do you have to pull dash panels? I dread pulling out dash panels, I'm afraid I won't get it back good and tight like it is now. Bout like door panels, I never can get those snapped back on good and tight without breaking a clip!

 

For panels and such, it's all about technique. Dash sections are pretty easy to remove, but I've parted out quite a few pickups. The dimmer I think is bolted to the dash (pull the knob off). You might have to unbolt the bottom kick panel/cover under the steering column to get to the connector. Reinstalling is just putting it back in the hole (I think it has a flat to clock it) and tighten up the nut and push the knob back on.

 

I have had to do this on a number of older trucks. It's always been the case of the rheostat issue. Just install a jumper wire and you'll know if you need to order a new one. Tony

 

Alright, I done some checking this past weekend. Checked relays, all good. Pull the rheostat switch out and check it, it was good. I noticed something else which lead me to believe that it's not the bulbs. The shift lever lights aren't working either (PRNDL). Surely the dash bulbs AND shift light bulbs didn't just decide to all blow? What are the chances!? I think I have some wiring issues, what do y'all think?

 

Repeat: 2) Broken connection from tail light fuse to the dash light circuit.

Are you getting 12V from your tail light circuit to your cluster?
How did you test your rheostat? Does the wiper have 12V/ Does one side of it have ground?

After 8 days of trying, a schematic is warranted.

 

Checking the rheostat switch all I did was pull the plug off the switch and put a jumper wire from terminal to terminal inside plug and it did exactly what the switch does, turns on the radio and climate control lights but not guage lights. I haven't pulled cluster yet to see if I'm getting 12v to the cluster as that was my last resort but looks like that's what I'm gonna have to do. I don't know if I'm getting 12v to tail lights I just assumed I was as they are working but like I said, I'm better mechanical than I am electrical. Just trying to figure out how all this electrical stuff works. I cannot find a good wiring diagram anywhere that shows the layouts in the harness that goes to the cluster

 

The toyota TIS site has wire diagrams, it costs $15 for 48 hour access, and you can download the PDF files (about 50-60 per year/machine). It covers 1990+.

https://techinfo.toyota.com/

If you're unsure how to test taillights to validate everything is working right, this might be a bigger project than you want to take on with out help. A multi meter is almost a must at this point (not a simple test light).

Generally for the instrument cluster the gauge lights (park neutral, drive, oil, check engine etc) are switched on the ground side of the circuit, and the power is fed to all of the lights all the time. The backlights (that lights up around the gauges when you have your headlights on) are the ones I was talking about before relating to the taillights in my situation.

Looks like the gauge lights (on a 92 pickup wire diagram) run off a 10a gauge fuse which goes though the integration relay then to the combination meter (instrument cluster), gauges and lights are grounded to give you the signal/light.

Here is a sample of what the wire diagrams look like from TIS and the wire layout diagram and connector locations. Screen shots are for a 92 pickup so not the same application.

 

Good job testing the rheostat...
But when you say

Yes, you are getting 12V to tail lights, to radio and climate control lights, but not your cluster light circuit. You definitely have to access the cluster circuit in order to find out where the 12V stopped.

 

Okay so what should I do, just pull the cluster and see if I'm getting 12v to the plugs that hook to it?

 

based on the 03 ewd.

locate jb#3,
disconnect plug 3c,
test for continuity between pin 11 to pins 12 thru 22 (specifically pin 16 power in, pin 14 to lamps)

Disconnect, plug 3a
Test continuity, pin 5 (lamps) to 4 (dimmer)