Tail light and Dash Lights DON't WORK
 

1990 4WD Toyota Pickup DLX.

The tailights do not work and the dashborad lights are out. The directionals and reverse lights work fine. There is power to the taillights and the dash. The 15 amp fuse do NOT blow.

I replaced the taillight relay, rheostat,ON/OFF switch on the sterring column. I;ve tested every fuse and they are fine.

All Fueses are tested and good.
checked liscense plate lights for moisture.
cleaned all contacts in both tailight assemblies.
replaced all tailight bulbs and dash bulbs.
I traced all wires in the engine compartment and they are fine. I traced harness under truck back to the ECM and they are fine and cannot find any cuts or breaks,
currently, have the entire dash in pieces and no shorts.

Am I missing anything. Does anyone have any ideas on what I can do.

Please Help....

Lenny

There is a round relay on the driver side kick panel right next to the fuses. Mine is an '85 so I don't know if it's the same. My cab leaks through the windshield and I've replaced this fuse a few times. Same symptoms, no dash lights and tail lights.

Response
 

I forgot to mention i already replaced the tailight relay.
In the wiring diagram I found something called a ECT switchtaht actually connects to the dimmer switch. As i understand it this switch is just for an automatic tranny but I have a 5 sped. According to the wiring diargram that could be the problem too. Does anyone have any thoughts ?

Have the lights ever worked? If so, what happened between the working and not? Have any aftermarket electronics been installed recently (radio, amp, CD player, etc.)? If so, that may be the cause.

Likely the switches attached to the dimmer are back lit and that connection is to the back lights on the switches.

Any updates to this? Having same exact issue- gauge lights out, tail lights out - everything else is fine- fuses not blown. Is there a relay that controls this somewhere?

Guys- I am seriously stumped here- I've checked all the fuses- the tail lights work when the brakes are used, but not when I turn the lights on. The gauge lights (Speedo, tach, A/C) do not work, but the ECT light and check engine lights work. Headlights work fine, also. I really need my truck to work. TIA.

As noted above, have those lights ever worked? If so, what happened between them working and not working? Any aftermarket radio or amp been installed? Is there any trailer light adapter installed? If so, check out those parts. I had a very similar problem when I installed a new radio in my '85. I ended up just rewiring all the power to that radio and abandoning the stock radio wires and the problem was solved.

Yes everything worked great- This just started about two nights ago- I installed an aftermarket radio and an aftermarket remote starter about two months ago. Everything was fine until the other nite when I was driving I noticed my dash lights were out. I guess I need to pull out my radio and start there....Is there a relay or fuse I could check that isn't located in the regular spots?

Hey fellas- anyone have any more input? I also installed LED blinkers- truck is still incapacitated- could use some more thoughts...

If it helps, its a 2001, and my lights won't automatically go out like they are supposed to when I shut the truck off and get out...

Any luck getting this resolved?
 

Since it has been a year, I am hoping you found the solution to your problem? I am installing an aftermarket stereo/nav on my '02, and just ran into this same problem. dash, parking, taillights, and license plate lights all stopped working after the install. I pulled the new stereo nav out and replaced original system and still cannot get my lights back. WTF? I am guessing I burnt a fuse, but can't find one. Baffling. headlights, brake, dome, and map lights all still work. Anyone have a thought on this?

Similar Problem, Tail Lights, 1990 Toyota Pickup
 

My Toyota Pickup's tail lights stopped working. I check the bulbs and the fuses and all are fine. Replaced the bulbs and fuses anyway, but still no luck. Heard that it could be the tail light relay so I bypassed it and both tail and dash lights come on. I got a new relay and replaced the old one only to find that it didn't solve the problem. I'm out of ideas as to what to do next. Any suggestions? Also, nothing new has been installed in between them working and not working.

Was anything electrical added recently? Like a new radio, or a trailer wiring plug or similar? If so, might look into those mods and see if that was the cause.

Otherwise, see if the tail light relay is getting power. Quick test is to put a finger on the relay then turn the lights on and off and feel for the relay clicking on and off. If nothing is felt, troubleshoot that relay control circuit and see if you can find out why it is not getting power.

Hey 4crawler, any good ideas where I could find a replacement relay. I went to Napa today and the relay they showed me as a replacement had the right prong arrangement but the body configuration was way off. I checked Rockauto, no luck there. I have something coming in to my Advanced Auto Parts but I not real sure they have it either. Help?

I found it online

Just curious if the pins were correct .

It would not fit because of the size?? Into where it needed to go.

The pins were correct on the Napa one but the body was completely different. After searching for it as "tail light relay" I found the exact replacement on rock auto.com.

A lesson learned. Just looking at the 15 amp fuse and determining that it is intact is not enough. Putting a tester on it is definitive. My problem was the fuse not the relay that I spent an hour to track down, Advanced Auto Parts comes through again. The Rock Auto relay should arrive tomorrow. Hopefully one of them will take the return, I'll just keep one on hand for friends or if I need it.

Yes, have run into fuses that appear OK yet have failed. Some have almost an oxidized look on close inspection, like the metal (probably aluminum) somehow corroded inside the fuse housing. Others must have cracked near the end leaving the visible center portion looking intact. Easy way to test is measure the voltage drop across the fuse (should be 0 volts). Have also had others that seemed blown, but after pulling, testing (fine) and reinserting, they have worked normally. I guess those had oxidation on the contacts that caused them not to work and just pulling/re-seating them cleaned that oxide off.

Yep...I like to set my meter to beep on continuity and then touch the terminals on the tops of the fuses. Much much faster and, as mainecrawler put it, 'definitive'.