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Old 12-19-2021, 11:36 PM   #1
'68OrangeSunshine
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Dash Light Gain uneven

When I turn up my dashlights via the headlight knob, they don't really come up until I'm near the end of rotation, then they pop on.
Can I pull the headlight switch out of the dash and spray it off with contact cleaner [Blue Shower] of do I just replace the whole headlight switch assembly?
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Old 12-20-2021, 12:09 AM   #2
dmjlambert
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Re: Dash Light Gain uneven

Do you have LED dash lights or incandescent?
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Old 12-20-2021, 12:34 AM   #3
'68OrangeSunshine
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Re: Dash Light Gain uneven

I think they're incandescent, but there may be some LEDs. I'll have to check.
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Last edited by '68OrangeSunshine; 12-28-2021 at 10:57 PM.
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Old 12-20-2021, 02:12 AM   #4
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Re: Dash Light Gain uneven

I recommend make sure they are all incandescent and then see if the problem remains. There isn't really any such thing as a dimmable LED bulb for a dash, that operates using the rheostat built into the headlight switch. The supposedly dimmable LED bulbs dim "to a point" which means they don't dim very well or very much.
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Old 12-28-2021, 10:54 PM   #5
'68OrangeSunshine
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Re: Dash Light Gain uneven

Nope, all incandescent. I rang out each one, too. No opens.
Dusted off all the lamps.
Since I had the instrument panel off, I pulled the headlight switch and checked the rheostat action. It looked like the rotor terminal was not making contact with the whole rheostat coil thru the full sweep. On low settings, they are all dim, then the light flickers out. At 50 - 85% the dash lights are blacked out. Then at higher settings they all come back on.
I think the switch is defective. It won't make contact in the mid range.
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Old 01-07-2022, 01:06 PM   #6
67C10Step
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Re: Dash Light Gain uneven

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Originally Posted by '68OrangeSunshine View Post
Nope, all incandescent. I rang out each one, too. No opens.
Dusted off all the lamps.
Since I had the instrument panel off, I pulled the headlight switch and checked the rheostat action. It looked like the rotor terminal was not making contact with the whole rheostat coil thru the full sweep. On low settings, they are all dim, then the light flickers out. At 50 - 85% the dash lights are blacked out. Then at higher settings they all come back on.
I think the switch is defective. It won't make contact in the mid range.
I thought that was the way they all worked.😃

My 70 model as a teenager exhibited this same thing. My current 67 does as well but not as badly.
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Old 01-07-2022, 07:46 PM   #7
'68OrangeSunshine
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Re: Dash Light Gain uneven

Nominally, the rheostat from all-the-way counterclockwise, is supposed to come up from black, thru dim, to brighter and fully bright. Go past the detent stop and Dome Light is on.
If the cheezy repop switches don't make contact with the coil then it's a problem.
Looking at a $13 buck part from LMC. But if it's built w/o quality control in China, it may behave that way out of the box.
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Old 01-12-2022, 06:58 PM   #8
'68OrangeSunshine
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Re: Dash Light Gain uneven

Got a new switch at Auto Zone. Duralast.... $25 w/ life warranty. Made by Capitalist Chinese in Taiwan. Still AWM.
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Old 02-21-2022, 03:55 PM   #9
'68OrangeSunshine
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Re: Dash Light Gain uneven

Finally installed last night. Works good.
Continuous gain on dash lights from Black to fully Bright. No dropout.
New switch as not as smooth a pull from Off to Full, as the old one.
Not sure if that's a manufacturing flaw, or something that will break-in.
Duralast SW 141, p/n V19009, ''Switch, Interrupter.''
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