1957 power Trunk light Switch location ?

[Bill Balkie 24172]

Hello,
    i have noticed that my power  trunk light is out . Not the light on the dash but the light in the trunk itself . Replaced the bulb and it is still out . I can not find a plunger switch at all . then i thought it might work  with the solenoid that releases the trunk . Is anyone familiar with the switch for the trunk light and how it works ?

Thanks,
     Bill

[The Tassie Devil(le)]

I think you will find that the switch for the light is a Mercury one, that is within the light fitting itself.

As the trunk is raised, the small blob of Mercury within the unit, rolls toward the contacts, and creates the connection.   When the trunk is closed, the ball of Mercury rolls away from the contacts, and the light goes out.

Check to see if you have voltage at the light socket at the centre point where the light is.   Using a Multi Meter, set to DC Voltage, connect the point to a ground and read the meter.

If there is no voltage, then trace the wire from the light fitting, back towards the front of the car, till you find the break.

Bruce.

[Bill Balkie 24172]

Bruce , Are you 100%  sure it is supposed to be a Mercury switch ? The reason i ask the light socket looks original to the car  but does not look like a Mercury switch .  will check it out  tonight for sure . i have included a picture of a switch that is just like the one on my car .

  Thanks,
       Bill

[Bill Balkie 24172]

I think the dash indicator for the trunk along with the trunk light is controlled by the power trunk pull down . My Dash indicator light works fine , however i have no power to the trunk light .I do have a electrical schematic for the 57 Cadillac but it does not include the power trunk pull down . My problem could be as simple as a broken wire . But i am not sure about the wire that controls the light coming off of the power pull down .  Has any body else had this problem ?

  Bill

[Quentin Hall]

G'day Bill. It is a mercury switch . Be careful as it can fall out and break . . . I found out the hard way.Sometimes it can be as simple as a bit of verdigry on the contacts. Clean it up and make sure the screw holding it on is clean as it earths it to the body. Q

[Bill Balkie 24172]

Quentin ,
   Is the mercury switch in the light fixture . or somewhere else . I have included a photo of the light fixture .  I can not imagine it is in the light fixture but i have been wrong before .

  Bill

[The Tassie Devil(le)]

It is within the switch itself.   Not very big, as it doesn't have to be.

Bruce.

[57flw]

Bill,

This photo should help you.

Ken

[Bill Balkie 24172]

That is unbelievable , i would of never guessed that it had a mercury switch within the little light fixture .Well i have no power going to the switch but now  i know where the switch is . Thank you  57 flw , Quentin ,  and Bruce . now i can sleep again .

  Bill

[The Tassie Devil(le)]

Could someone have accidentally lost the internal part sometime in the past when changing a globe?

Bruce.

[Bill Balkie 24172]

Hello , Just checked the switch with a continuity tester and it works fine . turns off and on when moved up and down . for some reason the line is dead that runs to the switch . Maybe a broken wire . that wire should always be hot so that should be an easy fix .

   Thanks Again ,
    Bill

[R Schroeder]

Maybe wire is broke where it bends a lot by the hinge.