[RLZ]

Hey guys, new to site, new owner of a 2006 Chevy Silverado LT 4x4. The truck has several bulbs out in the tail lights. I can do bulbs, sockets, fuses and wiring. Here is my question ....... to ensure that all lights are working properly I need to know what the function of each is. There are 4 bulbs in each tail light, from top to bottom 1., 2., and 3 are all 3157 bulbs which are multi- function and #4 is the small 194 bulb. If someone can tell me what each bulb does I should be good from there.

THANKS FOR ANY HELP

 

[RayVoy]

This isn't tough, got the owner's manual?

The 194 is a side marker light
The 3157 behind the clear, guess what, back up
One red is signal and one red is brake

The low light filament in the red lenses would be tail lights.

Why is the backup a 3157, scale of economy I guess (for GM of course)

 

[RLZ]

Ok..... appreciate your fast reply ....and yes I am working on getting the vehicle owners manual ...... so not to be simply but the second buld down from top "Blinker" should that also have low light filament for tail lights ??? The blinkers work but that bulb is not lit at all unless brakes are applied...... Again thanks for the help

 

[RLZ]

So sorry I miss spoke..... I meant to say that the second light down from top 3157 "Blinker" only lights when blinker is used NOT when brake is applied ......

 

[RayVoy]

OK, there are so many variations, what does the other side do?

 

[RLZ]

Ray Thanks for our help and patience ....... Ok ...both left and right side do the same thing ..... I have everything sorted out except the Blinker Bulbs which are the second bulb down from top ..... the lens there are red, the bulb is the 3157 multi filament, on both sides this light only works as the blinker..... the second filament does not come on at all and it just seems and looks like it should also be on as a tail light but I don't know...and again both sides do the same thing .....the bulbs are new, the sockets are not corroded, so maybe it is supposed to be that way ???

Thanks

 

[JackE]

Drive around until you find a like truck then follow him until you figure out what his lights do, then you'll know what yours are suppose to do.

 

[RLZ]

And as a side note: I was able to pull the manual online.... they list the top bulb as stop lamp/ tail lamp..... and list that bulb (2nd down from top) as just "blinker" .... so maybe that is the answer .... it is just blinker ..... just don't want to get a senseless ticket....

 

[RLZ]

LOL .....JackE .....that's my plan if I can't get an answer hear .....!!!

 

[RayVoy]

The problem is with GM, the 1st time I saw what your dealing with, I had the same question.
Two filaments, why are they both not working?
GM is probably saving $1 per truck by using the same bulbs and not wiring them to do anything!!

Now, the good thing is that now you have the option of doing some custom lighting.
Wire the sockets so that all reds are tail lights as well.

Hmmm, sockets may be a problem, do they all have 4 wires?

 

[RLZ]

Thanks for all the replys ......the bulb in question ( 2nd one down from top, listed in book as "Blinker" has only 3 wires to socket and socket appears clean ........

 

[RayVoy]

Thanks for all the replys ......the bulb in question ( 2nd one down from top, listed in book as "Blinker" has only 3 wires to socket and socket appears clean ........

OK, I think you need 4 to have both filaments working.

 

[xPosTech]

Three wires for two filaments. Base ground and two contacts on base.

Ted

 

[RayVoy]

Three wires for two filaments. Base ground and two contacts on base.

Ted

Ted, that is true for the round base type bulb; but the flat base bulbs (like a 3157) is reversible, requiring a double ground

 

[RLZ]

THANK YOU ALL....... the lights are working correctly ........ the bulb in question "Blinker" is just that...... It is only a blinker......
JackE ........I ended up pulling in parking lot next to someone with an 03 with same tail lights...... ask if he could turn his lights on for me , running lights , blinkers, brakes......... just like mine....worries over !!! Glad I join this forum and hope at some point I can contribute some useful information