2006 H13 headlight bulbs not Fused?

[JBee]

I am wondering if anyone has any further information to explain how the newer style headlamps with H13 bulbs from 2006-on work for voltage control. I tinkered with the headlamps and came across to the conclusion there are no fuses for the head lights. Seems to be more electronically controlled system now than just a fuse and switch. I noticed that there is always a idle voltage on the high beams (approx. 11. 5V) even when they are off and 12. 5V on the low beam when they are on. When you switch the high beams on then the voltage switches 12. 5V high beam and 11. 5V idle on low beam. I have blown two sets of bulbs, first time I accredited it to cheap bulbs, but this time I plugged in my buddies 5th wheel to move it for him and it surged my lighting (I probably shouldn't have plugged it into the truck hot) but it blew both high beams and one low beam filament. I wondered why it blew out my high's since they weren't even one, then figured the filaments couldn't take the surge I suspect and acted as fuses since there seems to be idle voltage all the time on both so it could spike up. I will inquire to my local dealership as well to see if this makes sense as well. Thanks.

 

[sag2]

The headlamps (and many other circuits) are high side drivers from the TIPM (Totally Integrated Power Module). They duty cycle the current to give the proper lighting, and are internally protected from shorts to ground. A high side driver is just a solid state device that can control current flow. The trailer tow circuits are also high side drivers and when the trailer light circuits short to ground too often the TIPM shuts off the driver until the dealer resets it with a scan tool. The best part about them is they provide advanced diagnostics for opens and shorts.

 

[JBee]

The headlamps (and many other circuits) are high side drivers from the TIPM (Totally Integrated Power Module). They duty cycle the current to give the proper lighting, and are internally protected from shorts to ground. A high side driver is just a solid state device that can control current flow. The trailer tow circuits are also high side drivers and when the trailer light circuits short to ground too often the TIPM shuts off the driver until the dealer resets it with a scan tool. The best part about them is they provide advanced diagnostics for opens and shorts.

I figured there had to be some voodoo involved so I guess if the head light bulbs are less robust then some it's possible to overcurrent them? It makes me want to wire a relay to individual head lights to avoid such inconvenience and use the stock signal as a relay trigger only except there is >11V on both Low/High when on, so I guess a relay would be on all the time... . hmmm, always have to be different and I seem to find the bugs.