Re: Brake light issue
Posted by HH56 On 2016/6/17 21:52:23
I can think of two possibilities. One would be if the tail light bulb filaments are reversed so the tail light is using the bright filament and the brake light is using the dim. If that were the case it is possible the brake lights are working but not seen because the tail light is so much brighter. Not very likely that something couldn't be seen but is worth checking.
If wiring is stock, the power for the brake lights is being supplied via a fuse from essentially the same place the tail light gets its power. A more likely scenario is if both functions are trying to use the same filament or possibly a short is causing both filaments to be lit at the same time. In daylight when no tail lights are on the brake lights can energize the filament. When the tail lights are on the filament is already lit and when the brakes are applied it is like closing another switch in parallel. Since the bulb is already on the brakes can do nothing more.
Look in the trunk (or maybe underneath the car) near the left tail light. There should be at least two connectors similar to the one in the photo connecting a wire from the body loom to one from the left tail light and to a short loom running across to the other taillight. Coming out of the body loom it should be a black wire for the tail light filament and a green wire for brake lights. After the connectors, two wires should enter the sockets to supply the two filaments. Ground is via the mounting of the taillight housing. Not quite sure how turn signals were done in 41 (if you have them) but I think maybe a separate system or if part of the factory wiring, separate bulbs and two more wires out of the loom.
Make sure the brake and tail light wires are in good condition, connected to the proper filaments, and not shorted together anywhere.
Attach file:
(7.86 KB)
If wiring is stock, the power for the brake lights is being supplied via a fuse from essentially the same place the tail light gets its power. A more likely scenario is if both functions are trying to use the same filament or possibly a short is causing both filaments to be lit at the same time. In daylight when no tail lights are on the brake lights can energize the filament. When the tail lights are on the filament is already lit and when the brakes are applied it is like closing another switch in parallel. Since the bulb is already on the brakes can do nothing more.
Look in the trunk (or maybe underneath the car) near the left tail light. There should be at least two connectors similar to the one in the photo connecting a wire from the body loom to one from the left tail light and to a short loom running across to the other taillight. Coming out of the body loom it should be a black wire for the tail light filament and a green wire for brake lights. After the connectors, two wires should enter the sockets to supply the two filaments. Ground is via the mounting of the taillight housing. Not quite sure how turn signals were done in 41 (if you have them) but I think maybe a separate system or if part of the factory wiring, separate bulbs and two more wires out of the loom.
Make sure the brake and tail light wires are in good condition, connected to the proper filaments, and not shorted together anywhere.
Attach file:
(7.86 KB)This Post was from: https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=177911