The left headlight on my 2015 Fit went out. I tried a new bulb, checked the fuse, which was good, swapped out the left fuse with the right, left still didn't work, tried with the right headlight bulb, didn't work. I tested with a multimeter and it looks like theres no power.

Question is, is there someplace else upstream that I can check for a problem, or is this likely a broken wire? If it's a broken wire, is that something that's going to require a lift to get to, any kind of special tools, particular cuss words?

I'm leaving on a trip that's mostly going to be at night and my mechanic and the Honda dealer can see it until Sept 10. If i can fix it before then i'll be a lot happier.

 

Well....I can help ya with some clever cuss words, if ya like

 

Honda Service ExpressHmm.... If I am reading the very limited information available correctly, there are 3 headlight fuses, all in Fusebox "A" under the hood (the biggest one). Fuse #1 (20A) is labeled as "Headlight Low Beam Main" and because it's 20A it would appear that it is for both low-beam headlights. Each High Beam has it's own (10A) fuse, 32 (Left) and 33 (Right).

If your low-beams are not working on just one side, then the culprit is most likely the low-beam headlight relay, it's in that same fusebox, but not labeled on the lid. It is is shown here as Ref #8 Control Unit (Engine Room). If it is the high-beams that are the problem, it's the same, just a different relay.

Relays for headlight control are nothing new, cars have been using them for decades. That way the switch on the dash or on the column doesn't have to be heavy-duty enough to carry the 4-7A of current that the headlight draws. It just has to supply the 50-100 milliamps needed to activate the relay, and the relay can power the headlight. What has changed, is that in many modern cars, the switch isn't actually connected to the relay, in stead, the switch sends a signal to the Body Control Module (BCM, which is a small computer called a microcontroller) and the BCM sends the signal to activate the relay. The BCM talks to all the other microcontrollers in the car on a network called CANBUS, so actually, the switch might send it's signal to the BCM, but a totally different microcontroller might be the one that actually commands the headlight relay to activate....... BCM is a generic term, each manufacturer calls the microcontollers something different, but the concept is the same. Some cars have more than 10 of them scattered throughout the car. But I'm getting off-topic here....sorry. Without, wiring diagrams, it's very difficult to troubleshoot that sort of thing using traditional methods.

Since, thus-far despite my strong Google-fu skills , I have not been able to locate any wiring diagrams for the GK Fit, so I am relying on the parts list diagrams for the location of the low-beam relay. I still have no idea where the high beam relay is...... Neither Chilton, Haynes, or AllDataDIY have coverage for the GK (Chilton and Haynes suck for newer cars anyway...), so the only source of information I know of is Honda. For $10 per day you can access the factory service manual information (what a ripoff) at Honda's "Service Express" website. Honda Service Express

Hope this helps a little and sorry for being so wordy.....it's a failing I have.

 

I was able to find a database called AutoMate through my local library, and it had a wiring diagram. If I could read the symbols it would help.

I checked the 32 and 33 fuses and the interior fuse box, and all were good. Except i need to get new glasses if i'm going to get up in there again. I'll look at the 20A fuse but i think i have to wait to get to the service. Now i need to find out if its covered by the warranty. Thanks for the suggestions! :}