Strange electrical problem

I'm having a very strange issue with my taillights. I have LED taillights in my 2002 Tacoma prerunner, one of which the brake light has gone very dim. Dim enough that I got pulled over for having a brake light out.

I bought some stock taillights because I don't really care to make my truck look "cool" anymore, I just want it to work. Unfortunately, it doesn't.

When I plug both taillights in, with regular bulbs, the left side gives power to the tail light, the turn signal, and the reverse light. If my lights are off at the switch, the turn signal will flash, but so does my reverse light. If the lights are on, no turn signal flashing, and all three bulbs are illuminated.

It gets even weirder, because if I unplug the right side, the left side starts working correctly. I figured out that the left side has an extra red wire, I'm assuming that's for my third brake light. Unplug the third brake light, no change.

My LED taillights work just fine, other than one having a hardly visible brake light. Normal bulbs in the turn signals, an LED bulb in the reverse light, only because the LED taillights take a different bulb for the reverse light, and I don't have regular bulbs for them, just my really bright LED reverse light bulbs.

I've been reading everything I can find online, but haven't found anything that matches my issue. Does anyone know anything about auto electrical, who understands wtf is going on? I haven't got a clue. I think I have given all the details I can, but if any information is needed, I will try to answer any questions. I'm not really expecting a resolution, since it's hard to diagnose online, and probably will end up just replacing the right taillight, if I can find one.

Thank you.

 

YO
Man I had same problem when I installed new tails and mixed conventional bulbs with led bulbs

like taco was possessed
IIRC…..signal used, opo side flashed once, then turn signal side would blink fine but both brake lights would shut off(with lights on)

at last resort, I put ALL conventional bulbs on every socket……not a problem since

 

Ok I'll give that a shot. Just need to replace my reverse lights, so I'll get some in the morning. I hope it works.

 

I was 5mins away from re-packing new bought tails and returning…..UGH…PITA

Thank goodness it was the mixed bulbs
GL
Keep everyone updated plz

 

Do you have a trailer harness? If so, remove it and it will probably solve your problem.

You could also have a bad ground on the tail light circuit.

 

No, no trailer harness. If it was a bad ground, would my aftermarket taillights still function correctly? That's what confuses me, is I had no problems before, switched to LED taillights, then trying to switch back to stock, and the left side just goes crazy. All three bulbs lit up when my lights are on at the switch, the reverse light blinking with the turn signal, when the switch for my lights is off.

 

A bad ground can affect conventional bulbs and not LEDs. LEDs run on lower voltage so depending on how bad your ground is it may or may not affect your LEDs.

 

Well, I put regular bulbs in, no LED, and it did change something. Now the tail/brake light and turn signal don't work at all, and the reverse light blinks when I turn the blinker on. And it blinks fast, like the bulb is out, and it's very dim. So I'm stuck with the LED tail lights, with the right brake light out.

 

When I bought the truck, it has stock lights and bulbs. Working fine. Put LED taillights in, they worked fine. Brake light goes out, out stock back in, doesn't work.

A buddy of mine laughed at me a while back, saying everyone buys Toyota, because they're "reliable" and then spend all their time fixing them. That's exactly what this truck has been. One problem after another, after another. Luckily the engine runs great, but everything else about this truck has been a major disappointment.

 

My front turn signals still have LEDs, with the thing who's name I can't remember spliced in, so they don't blink fast, due to the lower voltage of LED bulbs. Would that cause an issue, in my taillights?

 

actually yes!

the PCM thinks the front bulb is out so you get hyper flash on both frnt/rear signals
you need a resistor for front
(i do have SwitchBack led signals in front of mine).......and i have 2 of these:

https://www.superbrightleds.com/led...signal-hyper-flash-warning-fix+packamt-Single

and yes
hazard lights will flash normal without resistors....but not one side

 

It sounds like a failsafe mode to make sure you have safety features (like turn signals) available if one bulb is out. You have an 02 and I think that's when the trucks started getting picky about bulb resistances... food for thought

 

Im having issues with my led tail lights, brand new superbrightleds, they work then dont work. I take it all apart. They are on. I shut them off and on again and nothing.. The glass bulbs work fine.

 

sounds like something is grounding out