1947 Cadillac back up light bulb

[Lincoln41]

Trying to find a back up light bulb. I tried #1129 and #1154 but they did not work.

[Jack Mcilwraith]

number 1129 should work,but 1154 is a double contact bulb and will definately NOT work.I am wondering what you mean when you say "it didn't work".Do you mean you put the car in reverse and the light didn't work? Or is the socket corroded.Is there power to the socket?

[Bill Ingler #7799]

Jack is right on the bulb as 1129 as this is number in the Master Parts book and the same as I use in my 47. Take the bulb out see if the socket is hot after you turn the switch on and put the car in reverse. If not, then check for power at the switch and go from there. If the bulb is good and you have power at the switch, then make sure your light assembly has good ground to the body. If my memory is correct there is a rubber pad between the light arm and the body so the only ground for the light will be where the bolt end, nut and washer are against the body inside the trunk. Could be as Jack said some corrosion under the washer giving a bad ground.