1988 4Runner Instrument Panel Lights Not Working

Hello, I have a 1988 Toyota 4Runner with no Instrument Panel lights. When using the dimmer knob, the A/C backlight lights glow but none of the instrument panel lights come on. Not really sure where to start. I read a forum that stated that the tail lights are on the same circuit. Not sure if that is true. Any advice would be appreciated!
Thanks!

 

Do any of the indicators light up in the instrument panel, like the turn signals, high beam, E brake, etc.?

 

Welcome to the forum.

 

All of the indicator lights work such as turn signals, e-brake light, high-beams. It's just the backlight glow doesn't function. When you turn the dimmer up you can see the backlights glow where the A/C is but nowhere else.

 

Remove the cluster and check the bulbs. IIRC there are three 194 bulbs that illuminate the gauges.

 

I have checked all of the bulbs and replaced them all with LED's they were not working before I switched them over.

 

Check the tail light fuse, if it is good, check the instrument panel grounds, bulb contacts, and the strips between the bulbs.

 

Okay! Thank you so much for all of this great help. is the tail light fuse located behind the driver side kick panel the 15A?

 

Yes the fuse block behind the driver side kick panel, hopefully you can see the fuse diagram.

 

The LED lights have are polarity sensitive. They only work one way + -. They may be installed in reverse polarity.

 

The A/C backlighting shows that the circuit is working properly. So then the problem is the dash or the bulbs.

 

Hello! I spent some time today checking out the fuses and they are all in good condition and not blown. I did a walk around of the vehicle and checked the tail lights and they are working. I think my next steps are to recheck the lights and maybe switch back to incandescent bulbs and I'll see if that solves the issue!

 

Well, there's the schematic. If the external lighting on the tail light fuse is working, but the lighting of the gauges isn't, it may be the wiring from the fuse to the gauge set, from the gauge set to the rheostat that controls the lights, or from the rheostat to ground. All the colors of the wires are marked on the schematic.

BTW, from what I could see elsewhere in the schematics, the AC switch light is on an entirely different circuit. Just because it's working, is no indication the gauge lights should or shouldn't.

I hope this s a small help...
Pat☺

 

This is correct. The A/C switch itself should only light up when activated.

So my question is, is the A/C switch lighting up? (the small square light at the bottom left of the heater control unit) Or is the light for the entire heater control unit that lights up?



My 2nd question is, does the light go out when turning off the dimmer switch? Is the dimmer dimming the light? or does it just go off and on?

Maybe it is the dimmer.

Here is the wiring diagram for the 88 with 22re

The dimmer is listed as Rheostat (Y) on the second photo.

 

@FarmRunner88 , did you resolve your issue?
i experience the same issue.