Headlights

[FrankenPine]

This seems odd...driving lights are yellowish..(not bright) high beams are great('cept for oncomming traffic) is the problem with the bulbs? or electricial ? Any guesses ? Wiring is aftermarket loom. New alt, good battery.

Fred

 

[Bill Blue]

Probably a bad ground.

Bill

 

[Nickodell]

Are your headlights standard sealed beams or halogen? Halogens run at a much higher color temperature, more to the blue end of the spectrum, and the other lights will look yellowish in comparison. I doubt if it is a ground problem (sorry, Bill ) as it would have to be bad grounds at every one of the lights. A bad ground an make one lamp dim, but not all of them.

 

[Bill Blue]

Are your headlights standard sealed beams or halogen? Halogens run at a much higher color temperature, more to the blue end of the spectrum, and the other lights will look yellowish in comparison. I doubt if it is a ground problem (sorry, Bill ) as it would have to be bad grounds at every one of the lights. A bad ground an make one lamp dim, but not all of them.

Nick, a bad ground can make two (or three or four or whatever) lights dim if the installation uses a single ground wire, daisy chained from light to light.

Bill

 

[Jeff Scoville]

Nick, a bad ground can make two (or three or four or whatever) lights dim if the installation uses a single ground wire, daisy chained from light to light.

Bill

True guys, but a bad ground would NOT only dim one side of the same bulb.
Brights would be dim as well as normal lights.
Must be something else but I can't venture a guess other than trying a different sealed beam altogether.
If different bulbs don't change anything I would look into the actual dimmer switch.

 

[Bill Blue]

True guys, but a bad ground would NOT only dim one side of the same bulb.
Brights would be dim as well as normal lights.
Must be something else but I can't venture a guess other than trying a different sealed beam altogether.
If different bulbs don't change anything I would look into the actual dimmer switch.

Jeff, of course you are correct. I read the post to mean he was using driving lights and THEY were dim. But after rereading the original post, I think you are correct. Almost has to be in the dimmer switch as both bulbs are involved.

Bill

 

[Nickodell]

And I was full of baloney. I thought by "driving lights" he meant side/tail/number plate lights. If he had halogen headlights they would be halogen main and dipped beam. But I still believe a bad ground is not the problem. More like a bad connection in the dipped beam circuit.

 

[FrankenPine]

I see I should have given a little more info, regular sealed beam lamps, yes I meant the head lights, I'll plug a new lamp into the socket to see a difference if not.. The dimmer switch is the likely culprit ? Thanks for the ideas, Fred

 

[Bill Blue]

I see I should have given a little more info, regular sealed beam lamps, yes I meant the head lights, I'll plug a new lamp into the socket to see a difference if not.. The dimmer switch is the likely culprit ? Thanks for the ideas, Fred

Yes. If not in the dimmer switch, then somewhere in the wire from the switch to the low beams. Bad connector crimp would be a prime suspect if the switch is okay.

It is hard to see how a bad ground could cause this, even if the lights have a common ground. But ground circuits are funny things, never underestimate their ability to cause weird problems.

If one headlight is acting funny, it could be a defective light. It is most unlikely to have two bad sealed beams, unless of course, they happen to be production "sisters". Never totally rule out anything!

Bill

 

[Nickodell]

Speaking of weird: By strange coincidence I experienced a bad main and dipped beam from the LHS headlight yesterday; just a dim yellow light like a Victorian gas street light. On taking it out of the shell I checked the ground wire against the frame and found an open circuit. When this happens the circuit essentially goes through both filaments in series instead of parallel, reducing the available voltage to each at 6v - hence the gloom.

Rather than fool about trying to find where the ground had gone bad in the loom, and being congenitally lazy, I simply drilled the shell, cut the ground wire from the 3-way lamp connector and soldered a ring terminal on the end, then attached it to the inside of the shell with a self-tapping screw. It has likely made Lord Rootes rotate in his grave but it works fine.

 

[FrankenPine]

just a dim yellow light like a Victorian gas street light.
Ahhh Nick, You really know how to "put it into words"
I fooled around with the switch / wires but get the same result no matter which terminal I put the driving lights on, they are yellow, the brights are bright on which ever terminal they are connected too. Installed new lamp same result, Next step, follow the wires and look for................?
thanks for the leads, Fred

 

[Nickodell]

The Joe Lucas Prince of Darkness bullet connectors were notorious for corroding and coming apart. If you loom is a replacement, presumably you have more modern ones. If not, that may be you problem on the low beam hot feed. If both low beams are dim, you need to start at the light switch end of the run.