Turn signal issue

I just replaced my head lights and taillights on my 2023 tacoma off road with form lights (halogen to led). When I only installed the taillights lights the turn signals worked. Then after installing the first headlight that side first would flash on the dash then turn off. After installing both new headlights the dash indicates the turn signal working but no lights. When I replaced the hazard fuse it goes back to only flashing once but not working.
I don’t think it’s hyper flash hopefully not bcm.
Any recommendations would be appreciated. Thank you.

 

Check polarity on each headlamp turn signal circuit? Sounds like the control module doesn't like something with those.

 

@Griz24 If you are getting one brief flash, then nothing, it is most likely too much load on the circuit. I am betting both of those aftermarket lights have 6 Ohm resistors in them. If the resistors are external, you might be able to do something about it. If they are not, you can still make it work, but its gonna take more work.

 

I just looked up the form taillights. It looks like the resistor on those is external? It also looks like you can unplug it. Try that.

 

Thank you so much for the advice. Dumb question but will that have the possibility of blowing the LED due to overcurrent and with the other fuse it would give flashing instead of on then immediately off.

 

While I can not say for certain, I am pretty sure that the resistor is parallel to the LEDs, not in series. They most likely used it to mimic the load of the incandescent bulb is all. There is a chance you will get hyper flash again once it is disconnected. If that happens, then you may need add some resistance back into the equation. I know, pain in the butt .
These trucks are kind of temperamental when it comes to hyper flash. But, it if does hyperflash with that resistor disconnected, then I would suggest replacing the resistor it came with with a smaller resistor from VLEDs. They make some 25 Ohm resistors that are built really well. You can probably even adapt the Form plug for their resistor to one that the VLR25 will plug into.
Try it out with the resistor unplugged, and let me know how it goes? If you end up needing to add resistance back, I can help there. But let’s see how it goes without it?

 

I disconnected the resistor and still nothing it indicates flashsing but no lights when I replaced the hazard fuse it only indicates once then stops

 

Wow. That is kind of unexpected, but not entirely unfortunately. While the front and back are on the same circuit, the resistance being applied to one or the other makes a difference. Do the headlights have an external resistor that can be disconnected?

 

No unfortunately they do not

 

Crap. That makes it a little tougher to get around. The best solution I can think of is running the front turn signals off of separate relays. There isn’t a good way to reduce the resistance if we can’t get to the resistor. We could try tying an additional resistor in series, but that will affect the forward operating voltage (making the lights dimmer), and I am not sure that wouldn’t affect more than the turn signal….
So back to the separate relay idea. This is how my truck is set up BTW, just in case you think it sounds crazy. Of course, my truck being set up that way may just in fact prove that? Anyway, the best option I think is to pull that turn signal load out of equation altogether. You will take the turn signal and activate a relay with it, so the relay does the actual switching. The ECU on the truck will only see the relay load, which means you will have to add some load back into it. On my truck I use (2) 25Ω resistors on each side in series, but one would be enough for this. I know I suck at explaining things, but the wiring would look something like this:

Pin 85, ground and one leg of the resistor
Pin 86, tied to the positive wire on the turn signal (tan or light blue), also the other leg of the relay.
Pin 30, battery
Pin 87, to the headlight turn signal input.

I know it’s a little more complicated that way, but it will work. Plus, you can add a crap-ton of turn signals down the road .
If you wanted a plug and play solution to it,or want me to draw it out, let me know. This is something I can build so you won’t have to splice anything.

 

Thank you so much for the help. I ended up putting oem back in and replacing fuse which worked. I am talking with form engineers right now probably going to either get a replacement or go oem led with the harness swap.

 

Glad to help. These trucks can be frustrating trying to stay between "not enough" and "too much" resistance. That goldilocks zone is pretty narrow.