Headlight Flicker - Dr. Diagnosis

When i run my headlights in the dark they have the tendency to flicker every few minutes but it only flickers for a second. it’s quite weird since they make a clicking sound (like a baby nursing 5 times in 1 second) and flicker and go back to normal… just wondering if it was an electrical problem or a battery problem. i bought a new battery for my car about 2-3 years ago…idk just wondering if anyone has an idea.

I just noticed my civic does the same thing, except my headlights get brighter for a second then dim back down.

In for an answer.

halogen or HID?

Halogen for me. Wouldnt HID most likely be failing ballast?

2004 Subaru WRX Car Light Bulb Size Guide

Low Beam Headlight Bulb Size: H1-55W
High Beam Headlamp Light Bulb Size: 9005
Parking Light Bulb Size: 168
Front Turn Signal Light Bulb Size: 7440
Rear Turn Signal Light Bulb Size: 992 (7440A)
Tail Light Bulb Size: 7443
Stop Light Bulb Size: 7440 or 7443
High Mount Stop Light Bulb Size: 921
Fog/Driving Light Bulb Size: H3-55W
License Plate Light Bulb Size: 168
Back Up Light Bulb Size: 7440
Front Side Marker Light Bulb Size: 168
Rear Sidemarker Light Bulb Size: 168
Ash Tray Light Bulb Size: 74
Map Light Bulb Size: DE3175
Dome Light Bulb Size: DE3175
Trunk/Cargo Area Light Bulb Size: 921

Sounds like a bad relay. Headlights drawn enough power that they can’t be controled directly by that little switch inside the car. When you turn the switch all you’re doing is supplying power to a smaller wire that powers a relay to snap open, allowing current to pass through the higher amp, heavy gauge wire going to the lights.

That clicking is most likely the relay fluttering between open and closed.

The relay is in the fuse box in the engine bay.

Could be the relay, could be a loose wire on the switching side of the circuit.

I’d replace the relay first, though.

Ill give that a shot. maybe swap it with one from somewhere else before I go actually purchase one.

Yup; I’d agree as well. Most likely bad relay or ground.

If you had HIDs and they were doing this, then I’d say Bad Bulb or an almost dead bulb.

I changed the main engine ground, it was pretty rusty. It still does it though. All the lights on the whole car dim and/or get brighter together. I think its usually dim and everything will get bright for a second then go back. I checked the alternator at idle and it had a consistent 14.5 or so for a minute or two.