Brake Light

[curtis_98]

I have 1996 Nissan pickup. The tail light on passenger side works but there is no brake light. Changed the bulb thinking that might be the reason. Still no brake light. Any opinions of what coulld be the problem. Thanks.

[BernieB]

Possible causes:

• Replacement bulb is also bad (check by swapping with other side)
• Bad socket
• Broken wire (probably right at the socket)

A test light will confirm the problem.

[curtis_98]

Changed the socket and tried another bulb. Still the same problem On new socket there are two black wires. Old one has green black and black. Does it matter if green wire is attached to either of the black ones on new socket?

[BernieB]

Originally Posted by curtis_98

Changed the socket and tried another bulb. Still the same problem On new socket there are two black wires. Old one has green black and black. Does it matter if green wire is attached to either of the black ones on new socket?

Yes, it does. Is this a dual function lamp, like an 1157 or 3157, or is it single function, like an 1156?

If dual function, each wire goes to a different element in the bulb (running light and brake light), and reversing them will reverse the functions (brake light will be dim and running light will be bright).

If it's single function then it's probably one of those plastic sockets that don't ground to the body. In that case, one is the hot and the other is the ground, and it probably won't matter which gets hooked up to which.

Have you tested the wires with a test light to see if you're getting power when the brake is on? If you are, and the bulb still doesn't come on, then you probably have a bad ground or the ground wire broke.

[curtis_98]

Yes it is a dual function with a 1157 bulb. The running light is sort of dimmer than the other side. So if I change the wires around the light should be brighter. the green wire should hook up to two black ones and the other black to black. Is this correct.

[BernieB]

Originally Posted by curtis_98

Yes it is a dual function with a 1157 bulb. The running light is sort of dimmer than the other side. So if I change the wires around the light should be brighter. the green wire should hook up to two black ones and the other black to black. Is this correct.

No, you have two leads coming from the socket, one for each filament in the bulb. The metal body of the socket provides the ground in that case.

How many wires are coming from the truck??

[curtis_98]

Three wires. Two black and one green

[BernieB]

Originally Posted by curtis_98

Three wires. Two black and one green

Ah, okay... The green is probably the parking light, and one of the blacks will be the ground and the other the brake light, but the only way to be really sure is with a test light clipped to the frame.

On the replacement socket, does it have two wires or three? If only two then you have the wrong one and will need to get the three wire version.

[curtis_98]

Socket has two wires and thanks for all the help. So I need to go buy one with three wires. Right

[curtis_98]

Socket has two black wires. So I need to go buy one with 3 wires right. So many problems with the wrong parts. Thanks a bunch