Got the rally lights harness put on along with IPF housing and hella H4 12v 60/55w bulbs and wow what a difference.

Ipf's on stock harness with adapters




IPF's on rally light harness

 

dude SMS harness's are legit for the people that don't feel like building one and messing with the resistors and capacitors… like me

 

Not familiar with this product. Can you post a link or PM me details?

 

Wow that's a huge difference. I have been wanting to do this with my IPF's. How are they at night?

 

http://www.rallylights.com/detail.aspx?ID=4887

 

Awesome actually the hella bulbs were really yellow looking without the harness now there very bright white with very little yellow tint

 

P.S. those pictures are both low beams by the way.

 

The SMS harness does an awesome job for incandescent bulbs!

If you put an oscilloscope on the stock H13 plug, you'll find that the feed is only high about 80% of the time - that's the pulse-width modulation Jeep uses so they can use the same headlight bulb for daytime running lights. Even worse, it feeds about 10.4 volts to the lights instead of the 14v or so that you should be seeing while the engine is running. So there's way more juice getting to the bulbs when you use a relay harness.

If you're running LED bulbs, a full harness isn't needed as the LED lights will run just fine on as low as 9 volts. You still need some adapters that have a capacitor and diode hooked to them to kill the flicker (LEDs can turn on and off fast enough to keep up with the PWM, although not everybody's eyes can see it), but those cost less than half of what the SMS relay harness does.

 

I'm curious to see how the extra power affects the bulbs life.

 

I'll keep ya updated the hellas were new when I put them In