Headlights not working

I got your wiring harness to upgrade to the led 2020+ headlights and my drl and headlights wont work. Turn signals and high beams work but nothing else does. Am I missing something?

 

Please post a photo of the connectors showing both sides of the wire and I’ll do a visual inspection.

note the DRL won’t be active until you release the parking brake.

 

Low beams are most likely flipped. You want red to red and blue to blue on those.

 

drls are working now. but still only high beams when stock is pushed forward. (normal working high beams)

 

Double check low beam fuses. Harness looks correct and a match to Oem. Double check terminal is seated properly in the connector and the connector is fully seated.

both sides have no low beam?

 

already checked all. fuse is fine and both clicked when plugged in. and correct both sides don’t have low beam. i’ll go ahead and check the fuses once again in a just a little. but i don’t believe it’s that. i did some tested and it seems as if the relay isn’t getting power which makes me think it’s a fuse but all the fuses are fine. any ideas?

 

Connect Oem low beam to harness high beam and Oem high beam to harness low beam making sure polarity is correct (the connector tabs will be improperly aligned for both) and observe. Since you’ve proven the headlights do high beams properly this tells you if the problem is truck side or headlight side. We would expect that low beams would now work with high beam on the stalk and high beams would not work (with stalk on low beam) if the problem is on the truck side.

Also, safe to assume your tests are with key set to ignition or PTS on? The ECU may be a little smart about things, my ‘16 MT is much less smart.

 

The low beams now work when I push the stock forward as I would for high beams. It is a push to start and all of these tests are being done with it fully running.

 

So that tells you a few things:

1. The harness is doing its job as instructed
2. Ground on the low beam connector is good (we already knew both power and ground on the high beam connector was good from initial tests)
3. The headlights work properly.

If you have a meter, the next step is to probe the low beam connectors and figure out why they don’t get 12v when the stalk tells them to.

 

Also probe the low beam fuses and check resistance / continuity if you have a meter.

 

@caribe makaira can you think of something obvious that I’m not considering?

 

I will check all of that as soon as I get home. Thank you for the help so far I'm really wondering what's going on

 

I'd say test the auto position by covering the sensor and also providing light to it. Just to discard that as pass or fail.

 

The lights are manual turn on and off. Would they really still have a sensor?

 

Found and covered the sensor so it would know its nighttime, no change. relay us pulling 0.02 so nothing. dimmer 20a fuse is no power but the dimmer relay is getting power.

 

Did you replace the Dimmer fuse? It's a direct connection (via bus Bar) to the battery.

 

The dimmer fuse isn't bad but I will replace it to test it.

 

replaced it. didn’t change anything. when out the high beams turn off as well

 

Was this ever fixed I ordered the wiring harness from FBC yesterday thinking the one I got with headlights might be no good and this could resolve my exact same issue 2021 Toy Tacoma TRD OffRoad stock halogen with LED DrL upgraded to The “C LED Headlight Assembly”, and I also have High Beams Flashers and DRL lights no low beams, I switched the connectors around and when I need headlights I turn on my high beams that output to the low beams in the assembly was the only quick fix for now but now I have no high beams doing that @daveeasa should I still be purchasing your harness if I have the same issue already, I thought it was bad wiring

 

Would you perhaps consider using punctuation? Very hard to read this.

To troubleshoot, start with photos of your connectors for high beam and low beam showing wires on both sides. The easiest mistake is swapping driver side high beam as positive is solid white while negative is white with a black stripe.

The harness is the same regardless of who you buy it from, me, TRS, eBay, etc. just OEM vs knockoff connectors, wire colors, extra grounds, labels and heat shrink and tubing differ.