Wiring-what Does This Do?

Just a comment - the transmission-mounted backup light switches are always a pain. Usually it's the connector that stops connecting, from what I've noticed. We have annual inspection here, and the backup lights have to work. They nearly always require some fiddling.

A resistor inline will limit the total current, but as mentioned, it will also act as a voltage divider and make the lights dim. A better approach IMO would be to substitute LED bulbs, which typically have a resistor in series with the LED and draw a lot less current. Incandescent bulbs draw a lot of current at turn-on , since the cold filament has a much lower resistance than when it's 'incandescent' (10x? 20x? something like that). This could be part of the issue. The two 1157s could be drawing as much as 20 or 30 amps momentarily when switch contact is made.

 

My system is 6v but I just installed these LED 1157s tail/stop lights to replace my incandescent 2057s. MUCH brighter than the 6v incandescents with a much lower power draw. I'm sure they come in 12v as well. The only drawback that I've had so far with these is that the difference between the tail and the stoplight brightness, while definitely there, isn't as dramatic as with the incandescents. There's a difference when you push the brake pedal, dont' get me wrong, but it would be better if the tail light brightness was a little less. Anyway, remember, these are 6v: 1157 LED Bulb - Dual Function 19 LED Forward Firing Cluster - BAY15D Bulb | Super Bright LEDs

 

I know it’s not the same animal, but ever since I had an in-line brake light switch catastrophically fail on my dirt bike, I’ll never use another one. It blew the top out and lost all pressure. Trusting the molded end with hundreds of PSI of pressure (and my life) when it can be avoided just seems silly to me. Find a way to make a limit switch work and be done with them forever.

 

Finally a solution!

 

How about installing a relay. Use the brake switch to trigger the higher amp load of the lamps. Doing so would also create brighter light emitted from the signal.

 

See post #30 and forward in this thread. Doubtful it would affect brightness much, unless the relay were close to the lights and the feed wire were larger gauge than the original harness.