Electrons flow. Volts make things go. Not running engine, just the lights on. I will have to snag a longer bit of 14 gauge wire to string to the lamp ground for testing.
I got no indication of voltage with the fuse in the holder. I removed the fuse to get some reading. Fuse was 20a (red) lowest row toward the seat, not firewall. I am headed to the MBCA gathering in the morning. They will be putting cars on the racks, and maybe this will get a diagnosis and remedy. clay On Mar 1, 2013, at 7:37 PM, Jim Cathey wrote: >> Headlight for low beam is only getting 10.98volts >> Headlamp for high beam is getting 11.16 volts > > So does this mean it's working again? That voltage > drop (is this engine-off?) sounds plausible for R107. > See: http://userweb.windwireless.net/~jimc/JSLlights.html > Relays will cure a lot of this drop, making brighter > headlights. Our 450SL had 400W of high beams when we > sold it. Take that, deer! > >> Fuse box shows 11.52 volts flowing from one end of the fuse holder to the >> other. > > Your terminology confuses me. Volts don't flow, amps do. > Does this mean that you measured 11.52 volts (to ground, > lights on) at both ends of a fuse? Which fuse? I would > expect some slight drop across the fuse if current was > flowing. > > The simplest and most direct measurement is to leave the > engine off and turn on the lights, then put the positive > meter probe on the center post of the battery + terminal > (not the clamp, the _post_), and the negative meter probe > on the lamp's non-ground contact. Measure the voltage drop > directly. It's surprising how much it is, and ought to be > around a volt. > > You can do the same between the battery negative post and > the other filament lead on the lamp. Usually the ground > side has much less voltage drop. Add the two readings, > then measure the battery voltage directly (lights still on) > and figure the percentage voltage loss of what the battery > had available. You'll be surprised, I know I was. (It was > 10%, for a 30% reduction in lumens! And a concomitant > 300% extension of bulb life.) > > -- Jim > > > > _______________________________________ > http://www.okiebenz.com > For new and used parts go to www.okiebenz.com > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
