okay, need some help here tired of being harassed by johnny law. My tail lights are not brite enough when head lights are on while driving, hit the brakes there fine. running lights there fine. I have checked the ground, fine. im pulling 12.1v but when i pull the lights switch on i drope to half that and my tail lights are not brite enough, but like i said when i hit the brakes BAM there they are. Any suggestions?
Well, you have a major resistance somewhere. It's probably in the wire some where. You need to check resistance in the circuit, resistance in the socket, and resistance in the bulb. 6 volts is a lot to lose. Where are you measuring the 6 volts at?
Thnx Roadrunner, my neighbor and i traced the path. believe it or not but the harness had i shit you not from the alternator to the inside of the fire wall, 1og wire then butt spliced to 12g to the fuse block. my neighboor was all umm thats shoving 10 punds of poo into a 5 pound sack. well i fixed that and nope. So we have traced all of it back. and it still does it. Now one added scenario i forgot to mention. the power side of the light switch's c/b get holy batman hot. do you think my switch could be bad? it is original.
Yeah, there sounds like there is major resistance there. Measure the voltage right after the switch, and that will tell you if that's where the resistance is.
Measured from the light socket direct when key is in accessory position, switch off im brakes on fine voltage. switch to running light position voltage fine, lights on bam drops. no bueno
You have one or more of the following problems: Wire gauge too small, poor splices (resistance too high), poor grounds, poor contacts somewhere. Unfortunately there are so many possibilities that no one can say 'look exactly here, and that is the problem'. Divide and conquer. Start at one end and start improving grounds, redoing splices, disconnect one component at a time to see if the behavior changes, etc., etc. You will kill a couple of hours but you will find it. If all else fails install a Bosch relay for the headlights with their own battery feed. This is a band-aid solution since you should still find the poor ground or whatever.
Don't forget the switch like he mentioned. There is very possibly some corrosion on the inside contacts of the switch causing unwanted resistance. That would account for the voltage drop and the heat that he mentioned. Although I would also bet there are poor grounds and wire splices in there too.
Ahh haa roadrunner is onto something, i pulled the switch and turned the dimmer theres turqoise corrison on the contacts, ill be heading to the car shop in orange to pick up a new switch. and check all my splices and grounds to boot. merry xmas everyone. and thnx for all your help.
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