Announcement

Collapse
No announcement yet.

48 Map light switch

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Electrical: 48 Map light switch

    Does any one know how the map light switch is grounded? The switch has a bullet style connector on one side and a small post on the other side. I have the bullet side connected and the light comes on. I can not get it to go off until I ground the post side of the switch. Just curious how it was grounded as I did not take it a part.
    Thanks for any help.

  • #2
    2R map light switch

    I too hope to find the issues with these. I have cleaned my switch and it works with a meter.. I put the ground wire in the bullet hole connect. The bulb. 1 filament 2 pin bulb in socket with the ground wire going through the switch and the hot on there to hot.. and nothing...

    Comment


    • #3
      If it's on a Car, It must be in Series with the Dome Light.
      Studebaker (and Older Car) Dome Lights are unique; the Door Switches Ground it to light, and the Manual Switch Switches the POWER to light it, the Bulb Socket is Isolated. That is why it has a TWO Circuit Single Filament Bulb with NO Case Ground.

      ________________________________________________________________________________ _______________________________________

      PSB: Of course the Truck Map Light maybe is SUPPOSED to be an ordinary Single Contact Bulb I think, doesn't it just get the Power Switched and has No Dome Light, or Door Switches?
      Last edited by StudeRich; 07-01-2021, 09:20 PM.
      StudeRich
      Second Generation Stude Driver,
      Proud '54 Starliner Owner
      SDC Member Since 1967

      Comment


      • #4
        ^ These do use the same two terminal bulb setup as the cars- so correct bulb number is 88 for 6 volt, or 94 if it's been modified to 12 volt. These are 15 candlepower, and the same physical size as a tail/brake bulb. The later cars with the plastic lens dome light use a 1004, which is a 12 candlepower bulb that's smaller than the 88/94. The 6 volt analog to that one is 210.

        The dome (map) light circuit on these (and most other older cars) is hot all the time, and the ground side is what's used to turn the lamp on, by completing the ground through either a door switch or the switch on or near the map light. It doesn't matter whether the body of the map light is grounded; the bulbs used in these ground through one of the two terminals instead of the metal base on the bulb. If your switch is grounding the circuit, then you don't have power to the other side of the circuit.
        Whirling dervish of misinformation.

        Comment


        • #5
          Thanks it is for a 1949 truck. I have been working on it for hours.. No overhead light.. But there is door switches. PS, It is also 12 V Neg ground.. I wonder if one should change the switch to hot and not the old neg side?

          Comment


          • #6
            The switches do have to be on the ground side, whether that's positive (originally) or negative (now), or it will just short circuit and blow the fuse whenever you open the doors
            Whirling dervish of misinformation.

            Comment

            Working...
            X