cybertech707

hey im a noob here and came across a little issue with my parking lights and dash lights. I bout the truck a 1992 regular cab 22re with 193xxx miles on it. i love the truck. so i decided to add a new stereo in it and power locks. I installed the locks and head unit on the same day. the next day the car had problems starting. and after a couple days i got in the truck and tried to turn the lights on and i didnt get no parking lights or dash light. the only thing that worked was the head light....turn signals and brake lights and reverse lights work fine and all fuses look to be intact. WHAT SHOULD I DO??

cybertech707

no one?

yoterr

well i had a similar prob in my 86 the tailights wouldent come on nor the dash lights but the brake lights did... i took apart the dash to find a burnt up wiring harness $15 bucks off ebay and about 2 hours time and fixed, but sorry to say if thats your case its not going to be that easy cuz you have EFI n such...just poke around under the dash, maybe pull the cluster ( thats where mine was burnt up) and see it something cut into it and its grounding out maybe? what did you tie into when installing power locks? and did you tie into anything when you put in the head unit??? just some things to check out

cybertech707

I pulled the dash and checked couldnt find any burn harnessed or grounded wires. i taped into the ignition wire for the power locks. as far as the head unit goes i didnt tap into anything else. is there a parking light relay? could it be the switch on the left side of the steering colum?

t0mwat3r

fuse...

http://www.4crawler.com/4x4/4R_TechI...tml#Electrical

4Crawler

iTrader: (3)

Do not tie the radio back light into the dash light circuit or what you describe will happen. Same thing happened to me with a new radio in my '85. I re-wired the radio to get power for lights and such from a new dedicated power and ground circuit I added and no problems since.

cybertech707

all fuses are good

cybertech707

i used the harness from the previous radio. i should re-wire the radio to get power from another source? what source would be good?

4Crawler

iTrader: (3)

Problem is most radios and electrical devices are set up with a back light power line and an internal case ground. Toyota dash lights are wired such that the dimming lights have a common 12 volt power feed, but they have a FLOATING ground connection via the dimmer rheostat. Tie a hard ground circuit to a floating ground circuit and bad things can happen (BTDT). What I did for back lights was hook into the parking light circuit. That way I get a back light that turns on and off with the parking lights, only thing you lose is the dimming feature.

Or for an easier connection, just tie the back light to the switched power line, then it is on all the time. During the day, you can't tell, during the night, it is on.

cybertech707

Then i still have the problem of my tailgate lights not working.

Ron Helmuth

on your year of vehicle one bad bulb can cause the others to be out. May be a combination filament bulb-it functions as a stop and tail light with the same bulb but different filaments.

Pull one taillight and check all the filaments-better yet swap in a new bulb. And of course you likely guessed the wrong side so be ready to do both.

heliax007

4crawler- I am having this exact same problem on a 2001- dash lights and taillights/parking lights out. Brake lights work and reverse lights work. Checked fuses with multimeter, in cab and in engine- all good. Swapped all relays, musical chairs style when I could.

I installed a stereo, but it doesn't have a dimmer feature, so I left the orange from the harness disconnected- does that need to be grounded? It is not shorting on anything, I capped it off.

I have pulled the entire truck apart trying to figure this out- I am hoping that what you said above is the problem- thanks

4Crawler

iTrader: (3)

It is not so much the dimmer line, it is the back light feature of the radio (assuming it has such a thing). Easy check is to unplug the stereo and see if the rear light start working. If so, that is the source of the problem.

heliax007

My radio doesn't have a dimmer- so question is, should I ground the wire coming from the truck? Also, I yanked almost everything out one at a time and tested- the radio, the tailights, the tow harness, the lightbulbs, etc....this is one of the most confusing problems I have ever had with a car. I'm completely out of ideas at this point- I even reached in behind the ecu on the passenger side and swapped that relay out. The last thing I have to swap out is the DRL relay, and I've not had power to that in over 5 years.

4Crawler

iTrader: (3)

Best bet would be to get ahold of a Factory Service Manual wiring diagram for your year vehicle and a volt meter or test light. Then start checking out from the battery to find out at what point you are not getting voltage to those lights. Basically you are starting with all that wiring, assuming good voltage at the battery and no voltage at the lights. Then pick some point about 1/2 way between those two points. If good there, then move towards the lights, if bad then move towards the battery. Retest 1/2 way between the last test point and the good part of the circuit. At each step you are eliminating 1/2 the wiring from the equation and keep dividing down the circuit until you find the point at whech things go from good to bad.

heliax007

A friend and I troubleshot this down to the signal that is sent from the ECU to the "TAIL" relay. We assume it should send a ground to the relay, because when we ground it out, all the lights come on as they should. Right now, there is a constant 2 volts to the relay from the ECU, and when we turn the lights on to the first position (parking light position, before full on headlights), there is 4 volts to the relay from the ECU. Does this make sense to anyone?