Why does my DRLs have two fillament?

[ChuckE]

On my H2, with 4157K DRLs in place, I found that the higher output filament is already being used. You can easily wire in the 2nd filament by putting in a jumper at the bulb plug.

The 2nd filament would use just 0.6 amps vs. the 2.23 amps of the main filament, the one that is in use. The additional 1.2 amps (having two lamps wired) is not going to exceed the relay already used to power on the current filaments).

You will notice a colored wire on one lead and a black wire on the other lead, with no wire on the center lead. Just connect a wire from the colored (the non-black) wire to the center connector.

BUT, it really is not going to gain you much. According to the spec of the 4157k, that 2nd filament is only about one tenth of the light output of the main filament (3 ft/candles vs. 32 ft/candles).

You will probably not even notice an additional 10% more light output. Forget it.