Electrical noob

How the fuck do I use one of these things to diagnose an electrical problem with my car? My left headlight isn't working at all and I just put a new bulb in it, but what exactly am I supposed to be testing for to tell what's broken here?

Continuity, seriously just Google "finding a short" also you probably need to check the socket itself for corrosion and or if the connector isn't bent or broken in some way.

Did you make sure everything is plugged in?

did you check the fuse? you need to check for power at the headlight connector so you might need a pinout to see which pin is 12v and then you put the black lead to a ground or unpainted metal. don't jam the tip into the front of the connector. you're supposed to backprobe it. google is your friend.

Use ohm meter to check for broken wires/discontinuous. Use volt meter to check if the light is actually drawing any power. Use the ammeter if you never want to use the ammeter again.

Set it to volts, 20VDC if not auto ranging

stick two leads into where light plugs in on the contacts

turn on lights

should see 12ish volts

if nothing then wiring or fuse is fucked

if yes 12-13 volts then bulb fucked

if less than like 11 then battery fucked

basically do you have voltage at the headlight, this is an overly simple explanation but basically how itll help you

If you put a brand new bulb in, then you're not getting power.

Grab the owners manual or look online for the fuse box layout.
You can check fuses by actually looking at them, which can be unreliable.

You can also check fuses with your pic related, the black lead goes to ground (the car's body is connected to ground) and then go over both contacts on each fuse.

Make sure you turn your lights on.
When going over the fuses, check both sides, if one side has voltage and the other doesn't, it's busted.

Godspeed.

none of the fuses are blown, that was the first thing I checked even before inspecting the headlight. I'll try what you've suggested though.

Everything is plugged in AFAIK

Alright, I'll do this and see what happens.

brb with results

guys

H7 Halogen or H7 LED?

Halogen feels and sees like piss yellow boring and weak vs bright LED?

LED has shitty beam pattern, if your lenses aren't made specifically for them, itll scatter the light either blinding on coming drivers or limit your field of light.

The best compromise is xenon HID bulbs.