Crazy Halogen headlight issue

I bought my 2018 SR5 this summer and truthfully only drive it to tow my travel trailer. I am not sure how often I drove it at night, maybe never. I have it in storage but took it out yesterday evening for a short drive just to run it a bit. Several people flashed me within 5 miles. I did notice the passenger side headlight looked more bright than the driver side. When I put it back in the garage I left the headlights on. The passenger light was definitely brighter and I discovered the passenger side was on high beam and the driver side on low. When I flipped the lever for high beams the passenger side headlight went to low beam and the driver side went to high. So evidently the driver side is working correctly and the passenger side is working opposite of what it should. I had a spare set of brand new halogens from a previous Tundra so I installed them hoping it was a malfunction of the old bulb. Nope, the new ones behaved the same. Any thoughts on what could cause this problem? A bad relay? A headlight control module? I want to get the OEM LEDs or the Form Lighting LEDs but I don’t want this to be an issue with them. HELP!

 

Can you check your VIN for service history and see if Toyota did the recall for halogen headlights? It required the replacement of part of the wire harness for the low and high beams, so it's possible the Toyota tech did something incorrectly.

 

Was 18 even included in that recall? I believe it was like 19-21 or 20-21. Could be wrong. But I will say after looking at the hack job they have to do to correct the halogen issue, I wouldn’t be surprised if they messed something up. I am glad I went with OEM LED.

 

Yeah, 18 was when the LED headlights were introduced and when wiring was changed accordingly. https://www.consumerreports.org/car...l-for-headlights-that-catch-fire-a1208906316/

 

The first thing I would do is bust out your DMM and see if the pins are correct.
Someone might have hacked up the wiring..
Unfortunately, you may have to pull the headlights out to get to the plugs...
I had to remove the entire headlight light assemblies to replace halogen bulbs, I got pretty good at it.
But no more since upgrading to OEM LED.








A8 is the left and A9 is the right headlight bulb plug.
Maybe you could do at least a visual check for the wire colors.

 

Yes, Toyota sent me the recall notice a month after I bought it. Evidently the previous owner ignored it but I’m not sure when the recall was originally issued. My local dealer did the recall when I had them change the oil this fall. The possibility of the tech screwing up crossed my mind. I can’t recall of a time that I drove the truck in the dark since I bought it…until last night. So I’m not sure there was a problem before the recall work or if it just started. Had I been flashed a lot before last night I would have remembered. Hmmm…

 

My guess is that the tech messed up to say it nicely. Have you seen the what they have to do for the recall? It entails cutting up the factory harness and re-splicing it back up. Take it back and have them look at it. High possibility the screwed up.

 

Thinking the passenger side bulb may have been the problem I YouTubed the Tundra headlight change and saw it wasn’t that big of a deal removing the grill and the panels to get at them. I had new halogen bulbs that I’d never used so I installed them and the problem was still there. Then the thought of the tech that did the harness recall messing something up crossed my mind. I took this picture of the passenger side harness. It sure didn’t look like it had been replaced and the driver side harness looked the same. Both were nasty looking and packed full of what I am assuming is dialectic grease. It looked like banana crème pudding. I took an air hose and blew out a bunch of it so I could see the contacts. According to your diagram above does this looked wired correctly? I left the ground (white with black stripe) alone but swapped the other 2 spade connectors and nothing changed except when the bulb went to low beam it was like half as bright as it should be so I put them back where they were.

 

That's really odd.
It seems to be correct as far as the colors go.
I'm at a loss.

You can find the full schematic for it here..
Ultimate TUNDRA Wiring Diagrams Collection | Toyota Tundra Forum (tundras.com)

 

Op where are you located? I have a set of oem halogen headlights from an 2014 that I can give you if you want to replace the whole unit to see if that works. I’m in Syracuse NY.

 

I’m in Ohio. My plans are to get OEM or Form Lighting LED headlights but I need to get this issue resolved before I pull the trigger. But thanks for the offer.

 

I have an appointment tomorrow afternoon with the dealership that did the recall. The service manager said the tech that did the recall will be checking out the problem. I am not sure I am happy about that….

 

I took the truck to the dealer today and as many suspected here, 2 wires were reversed when they did the wiring harness recall. The tech that did the recall work fixed the problem today and although I didn’t talk to him the service writer said the tech was extremely embarrassed and apologized for any inconvenience. I had a great lunch across the street with my wife, daughter and one of the grandkids while he fixed the issue so it was a good day!

 

Techs are human, at least they found it and owned up to it. And most importantly, got it fixed.

 

That is exactly what I told the service writer. I had no ill will towards the tech and pretty much said “sh!t happens. I did say I was glad the mistake wasn’t made on an airbag recall and we both laughed.

 

Now that this issue is taken care of I will share what I did when I got the truck home today. I had ordered a pair of Lasfit Pro Tundra specific LED bulbs ($130) and also a pair of Philips Crystal Vision Platinum halogen bulbs ($35). The Lasfits were a real pita and I could not get the driver side bulb to lock in to the supplied mounting plate so they are going back. Lasfit has a 45 day no questions asked return policy. I then installed one Philips CV Platinum and one slightly used Sylvania Silverstar Ultra in the other just to compare. HUGE difference…the Philips are considerably whiter. The Philips will stay in until I decide on either the Form Lighting or the OEM Pro LEDs. I am leaning towards the OEMs. I have read that $1300 Morimotos have fogged up within 2 years and am just afraid any aftermarket headlight does not have the stringent manufacturing standards as what Toyota does.

 

Glad it's fixed. The recall remedy does not replace and of the harness unless it is damaged. The cut the harness and install relays.

 

There was a certain batch of Morimotos that did have condensation issues but it was a couple of years ago.

 

So the condensation issue is resolved ?

 

I've had mine since Sept 2020 with no issues and they also have a 5 yr warranty.

 

That is great to hear….but dang $1300 is a lotta dinero…great looking lights tho.

 

Solid data points there. Did they actually fix the condensation issues or are you just going off your own experience?

 

I have not heard of anyone having the issue in quite a while. Morimoto did acknowledge the issue when it was happening though.