One Headlight Bright and One Headlight Dim

Swinger Ross · Aug 4, 2020

Hey guys, I just finished putting in a new 340 in my '70 Dart along with a firewall forward engine and light wiring harness. Everything works perfect except for my headlights, when I turn them on, the drivers side is lit up bright but the passenger side light is very dim. Any ideas? Thanks. I know its not the light itself and everything appears to be wired up correctly.

lilfontleroy · Aug 4, 2020

bad ground?
so you've tested it by switching bulbs left to right?

Swinger Ross · Aug 4, 2020

lilfontleroy said:
bad ground?
so you've tested it by switching bulbs left to right?

Yes I've switched them left to right, ground on back of light is making contact

lilfontleroy · Aug 4, 2020

Swinger Ross said:
Yes I've switched them left to right, ground on back of light is making contact

if the bulb works correctly on both sides then it's very likely in your wiring ~ somewhere.. at least you know what side it's on

A56 · Aug 4, 2020

Check your 3 prong plug to see if the plastic is cracked

tonysrt · Aug 4, 2020

Check voltage at the plug to make sure it's at least 12 volts or more.

Swinger Ross · Aug 4, 2020

A56 said:
Check your 3 prong plug to see if the plastic is cracked

Plug is brand new, not cracked

Swinger Ross · Aug 4, 2020

tonysrt said:
Check voltage at the plug to make sure it's at least 12 volts or more.

good idea

toolmanmike · Aug 4, 2020

9 times a bad ground

RustyRatRod · Aug 4, 2020

Swinger Ross said:
Yes I've switched them left to right, ground on back of light is making contact

So it's making physical contact. Have you checked it with the meter?

sabre67 · Aug 4, 2020

Make sure the 3 wires on the plugs are in the same location on both

Swinger Ross · Aug 4, 2020

RustyRatRod said:
So it's making physical contact. Have you checked it with the meter?

well turns out after all it was the ground, problem solved, thanks everyone

A56 · Aug 4, 2020

Lord Sparky · Aug 4, 2020

Sounds like my kids.

One Headlight Bright and One Headlight Dim

Swinger Ross

1970 Dodge Dart Swinger 340

lilfontleroy

annoyinglilLeroy

Swinger Ross

1970 Dodge Dart Swinger 340

lilfontleroy

annoyinglilLeroy

A56

MoPar Affliction

tonysrt

FABO Gold Member

Swinger Ross

1970 Dodge Dart Swinger 340

Swinger Ross

1970 Dodge Dart Swinger 340

toolmanmike

Moderator

RustyRatRod

I was born on a Monday. Not last Monday.

sabre67

FABO Gold Member

Swinger Ross

1970 Dodge Dart Swinger 340

A56

MoPar Affliction

Lord Sparky

Well-Known Member