Headlights dim when i hit the brakes...

[DasGoat]

So I have an interesting issue... When driving at night and i press the brake pedal, the headlights will dim for a split second, then return to full brightness. I replaced the battery a year or so ago, and it still does it. Do I need a new alternator, or is this just something that H3s do?

 

[SuperBuickGuy]

it's just something H3s do

the fix is an anti-flicker capacitor that you can buy with LED headlights.

 

[Zach]

Check the terminals on the battery and make sure they are tight. Very common. Ran into that with the 2

 

[alrock]

Yes, double check the terminals but it's normal on the 3s. Electric brake booster and the alternator is not always running. Takes a big amount of electricity to power the brakes and there's that momentary lag as the alternator kicks in.

 

[ZWilson07]

Yes, double check the terminals but it's normal on the 3s. Electric brake booster and the alternator is not always running. Takes a big amount of electricity to power the brakes and there's that momentary lag as the alternator kicks in.

Learn somthing new everyday, never knew h3's have an electric brake booster. So is there still fluid in the lines or what?

I apologize for the hi-jack OP.

 

[alrock]

Yes, still has normal brake fluid but no big vacuum brake booster. You can use your power brakes w/o the engine running as the battery will power the brakes vs. the engine's vacuum

 

[ZWilson07]

Yes, still has normal brake fluid but no big vacuum brake booster. You can use your power brakes w/o the engine running as the battery will power the brakes vs. the engine's vacuum

Awesome. Thanks for the info.

Carry on :cheers:

 

[persius1]

Thanks for bringing this up....I have experienced the same thing and never knew why.


Sent from my iPad using Tapatalk

 

[Best4x4]

Yeah I was impressed with the H3's brake setup especially after owning Range Rover's which had a similar $$$$$ braking system. One thing for sure each rig Rover/H3 have great brakes vs any Jeep I've ever driven. I'm very happy with my cross drilled/slotted setup and ceramic pads on the Alpha. Stops great, quiet, and they do run cooler vs the OEM.

As far as the brakes dimming the headlights I consider it a normal H3 thing. Both my H3's do it during braking (my Alpha is slightly not as bad), but if you use the flashers/turn signals and have an interior light on you'll see them basically flash with them lol. It's just an H3 thing.
:chuck

 

[DasGoat]

Thanks for the info!