My tail lights & DRL won’t come on. Brake lights, blinkers, headlights all work just fine. I have checked the fuse, it’s not blown. Getting power to all fuses, sockets to the light itself, & ground wire.

I have a 2012 TL.

The fuse has blown once and I replaced it, now they stopped working altogether.

I’m thinking it’s a wiring issue, but I figured I’d see if anyone else was having this issue and had a fix for it. or if you know which relay runs the tail lights, I can try that too. I can’t find the relay diagram anywhere only fuse box diagrams. TIA

 

Are you sure your left front side marker are working?
According to the diagram, they are sitting on the same circuit.

 

so I just double checked, right side is working, left side is not. Is there a relay that controls both of these?

 

There is no relay.
If fuse №27 above the driver's feet is OK, then most likely your module is fried.

 

like the light itself or the harness under the dash?

 

These are two different wires, on two different connectors, on two different harnesses and on two different grounding points. Do you think it was a coincidence and they were damaged at the same time? Is Fuse 27 definitely OK?

 

fuse 27 is fine. Fuse 15 is fine. Originally when this first happened, fuse 15 was blown. I have replaced it twice and that fixed the problem both times. The fuse is not blown this time but the lights aren’t working. They both went out at the same time, so possibly a coincidence.

 

Theoretically, some wire from this circuit is on the ground, and the MOSFET control unit reacts faster than the fuse and immediately goes into protection. I had such an experience with a short circuit on a Volvo. You need a multimeter to check the resistance of any wire in this circuit relative to the ground.

 

If you turn on parking brake, start car, the DRL will not go on until you take parking brake off. I changed my DRL to LED and I though I hit a fuse issue. I can't comment on rear light as I never noticed it on because you need to turn on all the lights to be on.

 

I finally gave in and took the car to Acura!

it was a fuse the whole time but it was a fuse for a fog light labeled (MICU) incase someone has this problem in the future, check fuse 27. I was changing 26 & 15 which were the two labeled for DRL and Left Front Small Light

 

Good job, you should have gone to a place where they know how to check fuses properly from the very beginning.