DRL, headlight(s), mystery wire

[billybee]

Hello! Long post bare with me. 2006 Honda CRV problem.

Ive had DRL problem for a few months. No DRL at all. It hasn't bothered me so I didn't bother before. Perfect timing as my driver side headlight burnt out last night. Both hi beams worked last night.

So I remove the under panel in the driver side and this 3 wire just falls out. Bottom right corner. Couldn't find where it attaches to. It's a 2 blue wires and a yellow. The DRL module is that grey box. I made sure the connection was tight, as the DRL warning light on the dash flickers at certain bumps on the road.

No work, so I check the bulbs. Like I said both high beam bulbs worked last night. Today few hrs later, the driver side HighBeam bulb doesn't work. I remove it and it's not burnt out, I switch that bulb to the headlamp, which is indeed burnt out, and it works. So i tested the bulb on the passenger side and it works both HighBeam and headlamp. Also the blue HighBeam indicator on my dash doesn't come on. I have spare H1 bulbs that are new and those don't work on the driver side high beam connection.

So I'm not good when it comes to electrical... So all the bulbs are H1, why would it work on one connection and not the other? I'll have to inspect the connectors. If it is indeed the DRL module would this cause one of the high beam bulb to not work? I've read the DRL are the high beams, just doesn't output the full voltage?

Tldr: DRL warning light
Inspected driver side bulbs/both not work
Tested driver side HighBeam bulb on both passenger HighBeam and headlamp which works.
Using the supposedly not working HighBeam bulb on driver side lamp now. All h1.
New spare bulb doesn't work on driver side HighBeam.
Mystery wire under dash that fell out removing panel

 

[Number_35]

@billybee, welcome to BITOG!

Some thoughts:

1. It's very possible that the disconnected dangling 3-port connector was for a factory option that your vehicle doesn't have. That is, it's very possible it came that way from the factory.

2. You need to get hold of a wiring diagram (electrical schematic) for your vehicle. This will be hard to troubleshoot without one. You could have a bad DRL module, or a bad headlight switch, or a fault with the wiring.

3. It is possible that the DRLs use the highbeam bulbs, running on reduced voltage. Mazda used to do that - back in the late-'90s I had a heck of a time troubleshooting our '90 MPV on which one DRL was out even though both headlights were fine. I finally checked a schematic, and found that the DRLs used the high-beam bulbs, one of which was burnt out.

Good luck, and please keep us posted.