Clock Stops When headlights Turned
Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC
The stock clock doesn't run on electricity. It's a mechanical clock that's rewound every couple minutes by relay so I don't think your headlights have anything to do with the clock stopping. If you're sure it's a stock clock from 67.
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Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC
I suspect your clock may have been changed over to a quartz clock before or during the restoration. If you find that to be correct, make sure the ground connection on the clock is good. With a stock clock about every two minutes or so you'll hear a loud click when it rewinds
If you disconnect the battery, the clock will continue to run until time for the rewind. If it has been switched to a quartz clock when you disconnect the battery, the clock will stop so you'll know for sure.
If you disconnect the battery, the clock will continue to run until time for the rewind. If it has been switched to a quartz clock when you disconnect the battery, the clock will stop so you'll know for sure.
Burning Brakes
Joined: Jul 2009
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From: ESCONDIDO CA
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Pretty sure that relay is reset by electricity. I still don't know how the headlight switch could affect that connection.
Thread Starter
Intermediate
Joined: Jun 2025
Posts: 46
Likes: 4
So, after speaking with the fellow who did the restoration the clock is original but was rebuilt with a quartz movement at some point.
He's going to check wiring diagram for a fix.
Thanks for every ones help, us newbies would be lost without it.
He's going to check wiring diagram for a fix.
Thanks for every ones help, us newbies would be lost without it.
Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC
Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
so according to OP the clock was restored with a quartz movement.. which means it needs constant electricity.. unswitched electricity.
Looking at my 67 wiring diagram: unswitched electricity is the clock, headlights, brake lights, horn, glovebox lights and cigar lighter..
unswitched electric connection occurs when turning on the headlights which turns on the instrument panel lights.. and the clock lights..
by unswitched, I mean you don't have to turn the key on to use these functions
are any of these functions effected by the headlights being turned on?
Looking at my 67 wiring diagram: unswitched electricity is the clock, headlights, brake lights, horn, glovebox lights and cigar lighter..
unswitched electric connection occurs when turning on the headlights which turns on the instrument panel lights.. and the clock lights..
by unswitched, I mean you don't have to turn the key on to use these functions
are any of these functions effected by the headlights being turned on?
Last edited by joewill; Oct 6, 2025 at 07:46 PM.
Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
I don't think a wiring diagram is gonna help you. There's only two wires 12 V and ground. the only thing that would affect the clock when you turn the headlights on as if the clock didn't have a good ground or it was dropping the battery voltage too low to operate the clock, which is very unlikely. Put s voltmeter on the 12 V lead on the clock and turn the headlights on and see what the voltage does and report back.
Racer
Joined: May 2002
Posts: 372
Likes: 11
From: Abilene TX
My clock did the same on my 67. It has a Quartz clock. I had the car worked on and the problem started afterwords. Turn on the lights and the clock stopped. Took out clock and found that 1 spade on the connector had pushed back and was not making a connection. Pushed the spade back in position and all was fine. I also made an extension on the clock harness to make it easier next time.