Headlights work and fuses are good but cannot figure out what's wrong. Running lights don't turn on when switching to first mode but headlights turn on when switching headlights on. Brake lights and turn signals work.

edit: This issue is now solved. The C440 connector on the back of the cabin fuse box was unable to be secured down and fully disconnected the red/green wire (D) from the headlight switch from the fuse box which made fuse #19 have 0V. Credit to lefthandedcat from the All Things Honda Discord server for helping me out with this issue and to everyone from this thread.

 

It’s the ILLUMINATION wire behind the aftermarket head unit. Properly cover it and replace the #15 10amp fuse underneath the dash fuse box

It’s the fuse marked in RED

 

Hey, thank you. I went over to this illumination wire and it was properly connected to the aftermarket head unit. I tried to disconnect it and cover it with electrical tape and replace the fuse anyway, but the instrument cluster, side markers, taillights, license plate light still don't turn on. I would like to add that the high beams don't turn on with the headlight switch and I have replaced the fuses for both high beams (L, R) and swapping the fuses for high beams and low beams the previously used high beam fuses work fine on the low beams and the previously used low beam fuses don't work on the high beams (the multimeter shows 0.25V when the low beams are on for both the high beam fuses but when the high beams are on the high beam fuses show 0V). That's something different than the current issue I'm having but I would like to mention it just in case if it's useful. Thank you.

edit: I haven't messed around too much with this car yet to know a lot but I suspect it could be dimmer switch (probably not because it's affecting exterior lighting) or just the headlight switch. I've cleaned the ground next to the cabin fuse box and the ground next to the passenger side headlight as well.

 

(With ignition on) All fuses with green above read 12V on both terminals for each and 18 is starter which I assume doesn't need to be 12V. 19 is tail light, instrument light, license light which doesn't read 12V on either terminal even after fuse replaced.10 and 11 are high beams L and R which only read 0.25V or 0.27V or 0.29V on both terminals when low beams on and 0V on both terminals when high beams on.

 

I have noticed too now that the dashboard time and head unit screen doesn't dim anymore when turning on parking lights (not working due to current issue) and headlights.

 

Have you tried another dimmer switch ? This won't help with the tail lights, but it may be your illumination problem.

 

I'll need to order one so I'll do that and try it out if there isn't any solution before then (I'll just have an extra dimmer if there's another/complete solution). Currently I have a headlight switch that should arrive today (01/17/2025 CST) so I'll be able to test that out if it's possibly the issue.

 

and the headlight switch was delayed to 01/20/2025... well I followed a how to guide from https://www.b18c5eg.com/how2/lightswitch and cleaned up the metal contacts but that still didn't do anything but I did see something wrong with the connector from the car. D, E and J terminals have a burn color around them (no melted plastic and the terminals look like they're fine) I'll be able to post a picture in a few hours.

 

 

^^^^ that will mess things up. Lol

 

lol yep but I did find out that's because in the past the past owner used LEDs that started burning it and they cut the high beam wire but I connected it back and now high beams work but everything related to fuse #19 does not. I tried jumping the dimmer wires (black and red (no black/red)) and not even that turned on the instrument cluster lights.

 

Something extra that I would like to mention (I wish I mentioned it in the original post) this all happened while I was driving home but I only noticed the instrument cluster lights turning off (this was during the night) so I'm lucky I didn't get pulled over lol everything was working fine then when I was 2 minutes away everything related to fuse #19 turned off

Shouldn't I be able to get the parking lights to turn on by jumping any of these terminals on the connector or does that require the headlight switch? I wasn't able to find information on anyone doing that.

 

This issue is now solved. The C440 connector on the back of the cabin fuse box was unable to be secured down and fully disconnected the red/green wire (D) from the headlight switch from the fuse box which made fuse #19 have 0V. Credit to lefthandedcat from the All Things Honda Discord server for helping me out with this issue and to everyone from this thread.