I have a 2009 Tacoma that has relay switched headlights. My best guess by looking at the headlight wiring is that it uses 20-ga wiring. There is a separate fuse and wire for each filament, but only one relay for high and low (fuses after relays).
I measured the voltage drop per the instructions on Daniel Stern's website. The truck was turned off, but both bulbs were installed. I'm not sure if that was a good idea (not having it running), but it was late and I figured the drop is probably going to be pretty much equal regardless.
The driver's headlight, both high and low beam, had about a .5V drop; .25V for ground, and .25V for positive.
The passenger headlight, with a much longer wiring run, had a drop of about .75V: .25V for ground, and .5V for positive (I think it was closer to .8V total).
The battery tested at 12.53V to start (which I started on the driver's side), and I believe it was clear down to about 12.1V when I was finished. So, it looks like I'm losing more than 5% of voltage--which as I understand translates to much higher light loss.
Currently I have a set of about year-old Osram 70/65W bulbs in the truck.
Would these numbers justify building a wire harness, or upgrading the factory wiring? I could probably run a heavy duty ground wire to the existing wires with practically no effort, but I don't know how much it would help. Solutions beyond that, of course, require more cost and effort.
I measured the voltage drop per the instructions on Daniel Stern's website. The truck was turned off, but both bulbs were installed. I'm not sure if that was a good idea (not having it running), but it was late and I figured the drop is probably going to be pretty much equal regardless.
The driver's headlight, both high and low beam, had about a .5V drop; .25V for ground, and .25V for positive.
The passenger headlight, with a much longer wiring run, had a drop of about .75V: .25V for ground, and .5V for positive (I think it was closer to .8V total).
The battery tested at 12.53V to start (which I started on the driver's side), and I believe it was clear down to about 12.1V when I was finished. So, it looks like I'm losing more than 5% of voltage--which as I understand translates to much higher light loss.
Currently I have a set of about year-old Osram 70/65W bulbs in the truck.
Would these numbers justify building a wire harness, or upgrading the factory wiring? I could probably run a heavy duty ground wire to the existing wires with practically no effort, but I don't know how much it would help. Solutions beyond that, of course, require more cost and effort.