View Single Post
Old 07-23-2018, 10:15 PM   #9
Erratic Member
autostaretx's Avatar
Join Date: Sep 2006
Location: Seattle
Posts: 18,494
Thanks: 3,228
Thanked 8,512 Times in 6,171 Posts
Default Re: DRL bulb replacement?

25 w/13.5v = 1.85 amps
13.5 v/1.85 amp = 7.3 ohms
12v / 7.3 ohms = 1.64 amps
1.64 amp * 12v =19.73 watts

Yeah, close enough to 21 watts...

--dick (bulbs are not "ideal devices", their resistance changes a bit depending upon temperature)
((yes, i could'a used W=V^2/R or W=R*I^2, but i felt like walking it through))
2005 T1N 118" Freightliner 2500 Passenger Wagon (2.7L, 15" tires, standard (short) roof)
Get YOUR Sprinter's full configuration datacard by entering your VIN to <-- lots of service documentation, Thanks to Jens Moller and Arnie_Oli
((as always: this post may go through a couple of post-posting edits... so maybe give it ten minutes before commenting))
autostaretx is online now   Reply With Quote