Hi I have a 67 coupe and my passenger side headlight is real dim. I tried a new pigtail and they are still dim. Also checked ground by voltage regulator it seems fine any ideas what i could do to fix this. Thanks
see what voltage your getting at the good light and then the poor light. one should be lower. trace that one all the way to find out were the bad connection may be. most times in the headlight switch itself.
I found the wiring on my 66 that goes from the drivers side to the passenger side above the radiator was hard and cracked. Replaced the old wiring with 12 gauge, installed relays and H4 bulbs and lights are very bright now
I checked to voltage between the two sides the dim side was .08 volts less switched lights and the one bulb seems to be going bad. Never saw a h-4 bulb just go dim. Problem fixed thanks: