Dash lights out?

Hey there. Finally got my truck after a little bit of waiting and am starting to tear into it a bit.

I am, however, trying to trace down a strange issue where the dash lights(instrument cluster and heater control panel) aren't working. The previous owner(a family member) never really drove the truck at night so he's not sure when the lights stopped working. I remember them working a couple of years ago when I last borrowed the truck, and I don't think any significant work has been done to it since then. I've done a little searching and torn into it a little bit and here's what I've found:

All fuses are good, including the panel fuse. Taillights/brake lights(which from what I've read are on the same circuit) are working like they should. Bypassed the dimmer switch and the same issue occurs. The only light on the dash that works is the one that illuminates the hazard switch.

The only thing I can think of(besides a bad ground somewhere) is the turn signal stalk is messed up and very loose. I can wiggle it and trigger the high beams, it's that bad. While the lights are turning on, perhaps there's a bad connection in the stalk that's causing this?

I'm hoping I'm on the right path on tracking this down. Any yays or nays?

 

I'm afraid the only way you may discover the issue is to open things up and start checking with a DVM.

I bought a car once that the lady felt was on it's last legs, none of the dash lights worked in it either. Turned out every bulb was burnt out!

@Jimmyh is good at diagnostics, @koditten has rebuilt a few of these. Maybe they'll have some simpler tricks to offer.

 

If it were the stalk switch the outside lights wouldn't turn on either.

 

Do just the running light turn on when you turn the stalk 1 click? You have to get our and check.

 

Here is the deal. Coming from the tail light fuse it taps off ( green power wire 12 volts ) and goes to a junction block. Out of that junction block you have several wires ( green power 12 VDC ) that goes to: Combination Meter Illumination, AC Control Illumination, Radio Receiver illumination, Shift Lever Illumination and Hazard Signal Switch Illumination. They all get 12 VDC from the junction block with the green wires.



Then you can see that the return for the Combination meter and the radio go through the Brown wire with white strip back to the Rheostat dimmer. The AC Control, Shifter and Hazard illumination returns via the green wire with a white stripe to the Rheostat. It is important to note that the dimmer rheostat controls the ground and not the voltage going to the LEDs.

I would check voltage at the green wires for the component that is not illuminating as you said above the Combination meter and the AC Controls. If they have 12 VDC you either have an issue with the components themselves ( not likely ) or a grounding issue between the component and the dimmer rheostat.

 

I'll double-check tonight, but I think they do. If they aren't, is there something I should check?

Thanks for the info! I should have some time to tear into things this weekend, but that wiring diagram makes sense. Looks like I can rule out the dimmer not working at this point. I also have a mess of aftermarket wiring where at some time or another a previous owner had an alarm system of some sort wired in. I'll be seeing what I can do to remove this as nothing's really hooked up now(this is a base model 2.4 2WD, poverty spec with zero options). Also there's an aftermarket stereo my family member did a couple years back; I wonder if there was something messy with the wiring on that end that might be contributing to this issue. As before I should have time to drill down a bit this weekend and see what might be not playing nice. Is this junction box something I can trace down from something like the hazard switch?

 

Were you able to track the problem down. I have a 2009 Tacoma Base that the heater and radio lights quit working. Fuses check out but I have to believe that this is quite common and someone has the simple fix.

 

Side question: Which of these wires would you tap to illuminate accessory switches when the headlights are on?

 

The green wire is power and the green with a white stripe is ground. NOTE: if you use those two wires the indicator should dim with the dash lights.

You could also use the green for power and then use any white with black stripe for a ground, then it will not dim with the dash lights.

 

I had the same issue when I first got my Tacoma. Apparently it's common when people install an aftermarket stereo to mistakenly connect the ground wire for the radio into the wire for the instrument lights. It isn't hot when the lights are off so it will work as a ground. When you turn on the lights it blows the fuse for the instrument lights (I think it's under the hood) but the radio works fine so it isn't obvious that they are connected.

I mentioned my dash lights not working to a mechanic and he immediately asked if it had an aftermarket radio and he fixed it in no time, so I guess it happens a lot.

 

I am having the same problem with my radio and ac panel. When I turn my fan switch on, the radio and ac control panel lights go out. I have noticed my dimmer rheostat is not working. Could the dimmer rheostat not working cause the lights to go out?

 

My dash lights went out while trying to override my starter relay. After checking all fuses interior, I started probing around the exterior fuse box under the hood. I discovered the “AM1” 40 amp fuse blown. I replaced and all dash power returned. Hope this helps the next guy.

 

I have a 2002 Tacoma extra cab four-wheel-drive four-cylinder, my dash lights all went out at the same time after towing a trailer, after tracking it down, it turns out my parking lights didn’t work either, and the whole thing boils down to a 10 amp fuse under the hood in that fuse box that runs the tail lights.