Green 88

DC electrical, my specialty.
Your dimmer switch varies the dash lights brightness by varying the ground for the lights, not the power. It's very common for alarm installers to incorrectly "tag" the dimmer wire in an effort to make the parking lights flash on those trucks (which usually destroys the dimmer switch). Often I'll find aftermarket stereo's light wires hooked up incorrectly to the cigar lighter light or ash tray light which also wrecks havoc on the dash lights. Green is the 12V side of the dash lights. Red/Black is the ground side. I believe the circuit will go from the tail light fuse to the dash lights, through the lights to the dimmer switch, through the dimmer switch to ground.

RAD4Runner

Agree with brian699 and Green 88.
Don't assume, that's how many of us end up with Runners with butchered electricals- the PO's or or amateur installers assumed. Always verify with schematics or ask if you're not absolutely sure.

Too bad that even that nctora-something site did not have the 89's. Do you guys know if 89 electrical is different from 86-88's?

RAD4Runner

Rets, I think Yotatech limits picture size. 800x600 pixels is decent. I've found a very convenient photo resizer that can resize by batch- meaning you drag several pics into it, specify what size you want new pics, then click OK. It has other features like putting text, etc. Try googling Fast Stone Photo resizer.

Green 88

I know there are differences but not in the light wiring.

RAD4Runner

Cool. Thanks, Green! Hope all's going well with your build.

Rets

Hey, guys, my Yota is a 91.... Thanks for all of your help. I had tried to get the manual from that site also and found it had been taken down. Does anyone had a schematic that I could look at? It's tough without although I will dive back in now that I have a few more tips.

LO, Got most of my dash out but put back the vitals to use to go to work this week.

Green 88

Checking dash light circuit.
Since your tail lights work the problem is not on the positive side of the dash lights. You can verify this by using a test light with the clip of the test light attached to ground, just check a dash light (behind instrument cluster, cigar lighter or ash tray lighter if so equiped) to see if it's getting power when the lights are turned on. The wire color will be green. If the dash light doesn't have power your tail light fuse is blown.
Check the ground side of the lights. Put your test light clip on a constant 12V power source so that when the test light tip is touched to any ground your test light will light up. Now take your test light to the ground side of a dash light that has been verified to be receiving 12V when the lights are on and check to see if the dash light is getting a ground when the lights are on, make sure you turn the dimmer switch all of the way in both directions. The wire color is either white/green or red/black. If you verify your dash lights are not receiving ground go to the dimmer switch with your test light still attached to positive 12V and do the same test. The white/black wire should have a constant ground and the white/green (or red/black depending on which colors are in your truck) should be a variable ground and you should be able to vary the brightness of your test light with the dimmer switch - if you can't the dimmer switch is broken.
If in your tests you discover the dash lights are receiving 12V power and a variable ground (depending on dimmer switch setting) then the dash light bulb is burned out.

Green 88

First you stated your truck is a '89 and now it's a '91. From your posts we don't know which engine your truck has, which trans, which trim level, etc... all of those factors can change the schematic required.