Dim headlights

FuryDan66

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So working on one bug at a time. So the headlights are terrible, I've seen flashlights put it more lol. New bulbs and I just can't figure out how to make them brighter. Could someone shade some light on this lol
 
This is a can of worms that could be any one thing or a combination of several:

1.) Low voltage from the battery to the headlights due to a weak battery, defective charging system or dirty battery cables. Older mopars had trouble generating enough power to run the lights with the 42amp alternator, the more accessories running, the worse it got.

2.) Corroded connections to the light switch, or corroded contacts inside the light switch.

3.) Corroded connections in the bulkhead connector

4.) Corroded or missing chassis ground to the body.

5.) Corroded plugs to the headlights

6.) Corroded connections to the dimmer switch or internal corrosion of the dimmer switch itself.

7.) Shorted or degraded wiring some place in the headlight circuit. Wiring that has frayed or is missing strands of copper wire is another possible cause.

8.) Corroded or missing ground to the headlights.

Dave
 
This problem is normally ground related if your charging system is working. You should see a ground wire coming from the right side headlight harness and secured on the radiator support. Make sure there's no corrosion on the connector or run a jumper wire from there to the negative side of the battery and see if it improves the light. If still no improvement check the headlamp plugs for corrosion. It's a matter of finding the resistance in the current flow. An ohm meter helps when dealing with electrical problems. If unfamiliar with ohm meters youtube is a good source for educational info.
 
I'm pretty sure like 100% there is no ground to the rad. I've pulled it out not to long ago and there was nothing. I'll look to make sure there isn't another ground somewhere. Thanks guys
 
Not "to" the radiator, but "near" the radiator. Probably should be ONE ground on each side of the car, for the lights.

CBODY67
 
You know I did see a ground sniped on the frame rail and maybe that's what it was . I'll be looking tomorrow ;)
 
Sorry been busy guys but I did find on the wiring harness there is one neg wire that runs off and is bolted to the inner frame.
So really not sure why the lights are so dim it all looks good.
 
Sorry been busy guys but I did find on the wiring harness there is one neg wire that runs off and is bolted to the inner frame.
So really not sure why the lights are so dim it all looks good.

Check your alternator output at idle, you might have a bad diode.

Dave
 
Ok will do but question tho.... even with the car off it dim so wouldn't the alternator only affect it while it was running?
 
Ok will do but question tho.... even with the car off it dim so wouldn't the alternator only affect it while it was running?

Yes and no. If you have low voltage with the car off and the alternator does not charge properly, you will have dim lights in both instances. Check your voltage with the car off, then start the car, it should jump by about 2 volts if everything is working properly.

Dave
 
Ok thanks ;)

While you are doing voltage checks, have somebody turn on the headlights and see if your voltage drops into a big hole at idle and run, probably indicates a bad diode. An alternator with a bad diode will give you 5-6 amps charge which is not enough to run the headlights or heater blower.

Dave
 
A failed diode will also let voltage run the wrong direction in the alternator, usually draining the battery over several hours time. That happened a few times on our '66 Newport. Always in an inopportune time. Luckily, the local dealer was still open and put a new diode in pretty quick. Saved the day a few times!

PLEASE be sure to clean the battery terminals and the inside of the cable ends. On a late-model vehicle, dirty connections there can lower the load check results by about 10%. Of course, with 150amps to start with, not a big deal. With 36amps, it can be.

What about the REAR lights? Discounting the fact there might be some dust on the lenses and reflectors, are they all of even brightness, too? Or dim? Just curious.

CBODY67
 
One of the reasons why i put in a headlamp harness with relays included and put in modern day halogen bulbs.All plug n play no hacking of anything.

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https://www.putco.com/lighting/wiring-harnesses
My Hella Lights :: Vision Plus 5¾" Conversion Headlamp
 
Daniel Stern's lighting website www.danielsternlighting.com has many interesting lighting alternatives, including how to wire the lights to use relays such that full battery voltage gets to the headlights. Previously, relays were used to fun the 100W "driving lights" (some of which were converted aircraft landing lights) or some of the "Oscar" dedicated aux driving lights.

He even found a way to wire-around the Chrysler computer voltage regulator (part of the larger body computer) and use a 1970-era Chrysler free-standing voltage regulator instead. Might not work in all cases, but it did with his Dodge pickup truck. Your results might differ.

I've used "E-code" lights for several decades. Never did see the need for using them on relays as they were plenty bright as is. Main thing is that their beam pattern is different than what we're used to, putting more light down the road than up close (as USA sealed beams do, which can lead to a false sense of security, sometimes). That beam pattern does take some getting used to, though, but much better for night driving. They will need to be re-adjusted when replacing sealed beams, too! Their much sharper horizontal cut-off allows them to be aimed "higher", relatively so, than sealed beams (and their "everywhere" beam pattern). I consider the E-code lights to be a much better alternative to the LED lights many seem to like for their "brightness". Better than projector beams as they have enough upper-beam scatter to hit street signs and such without affecting the other drivers or needing "hi beam". Just my experiences with Cibie E-code, Cibie Z-beam, and later SEV-Marchal and Hella headlights.

CBODY67
 
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Thanks man, doesn't seem like the kit is to expensive.
For what it is worth,simple plug n play and piece of mind.
I had sold and installed dozens of the harnesses and got nothing but positive feedback.
No more flickering,no more dimming at idle or when hitting the brake or turn signal.
No more high amperage draw on the foot dimmer and ditto on the headlight switch.
The relays take the brunt of the load and are generic relays that can be found anywhere should they burn out.
I have yet to replace any of the relays
Just constant power and bright lights.
Hope this helps.
 
Daniel Stern's lighting website www.danielsternlighting.com has many interesting lighting alternatives, including how to wire the lights to use relays such that full battery voltage gets to the headlights. Previously, relays were used to fun the 100W "driving lights" (some of which were converted aircraft landing lights) or some of the "Oscar" dedicated aux driving lights.

He even found a way to wire-around the Chrysler computer voltage regulator (part of the larger body computer) and use a 1970-era Chrysler free-standing voltage regulator instead. Might not work in all cases, but it did with his Dodge pickup truck. Your results might differ.

I've used "E-code" lights for several decades. Never did see the need for using them on relays as they were plenty bright as is. Main thing is that their beam pattern is different than what we're used to, putting more light down the road than up close (as USA sealed beams do, which can lead to a false sense of security, sometimes). That beam pattern does take some getting used to, though, but much better for night driving. They will need to be re-adjusted when replacing sealed beams, too! Their much sharper horizontal cut-off allows them to be aimed "higher", relatively so, than sealed beams (and their "everywhere" beam pattern). I consider the E-code lights to be a much better alternative to the LED lights many seem to like for their "brightness". Better than projector beams as they have enough upper-beam scatter to hit street signs and such without affecting the other drivers or needing "hi beam". Just my experiences with Cibie E-code, Cibie Z-beam, and later SEV-Marchal and Hella headlights.

CBODY67
I agree that the newer LED's are not up to snuff.
most have big butt ends for cooing fans or heat shrink.
Stuffing new LED bulbs in E code lights may not have the clearance BEHIND the headlight and the body.

I have HID's in the wagon in vintage Carello housings...very nice.
But I always revert back to and lean on the Hella housings with H4 low beam bulbs and H1 High beam bulbs.
They do throw light in an impressive distance.
Besides,should I need an H4 or H1 halogen bulb I can practically buy one anywhere.
HID's I had to order bulbs--even had to diagnose whether it was a bulb or a ballast.
Pain in the arse,really.
 
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