No turn signal and no break light

Officialerickm · April 12, 2018

Hello I am new to this and wanted to ask for some help. I drive a 2007 silverado nnbs 5.3 LT 4X4 ext cab. I currently have an issue with my left turn signal not working. It starts to flash rapidly on my dashboard but no actual light outside. Also my left break light does not light up when I press on the breaks. I changed all the left side bulbs on both front and back. I changed the break switch sensor, I checked all fuses that are located on the side of the drivers dashboard. I was told to change my positive battery cable to 2ga. Also I read that I could change the turn signal flasher but when I look at th fuse box in inside the hood, I can’t find it! Will I need to replace by BCM? Idk what to do, has anyone have this issue in the past! Thanks!!

Colossus · April 12, 2018

If you have a trailer lighting plug on the back of the truck, check that out. Very common for those wires to go kablooey.

carnau · April 12, 2018

10 hours ago, Officialerickm said:

Hello I am new to this and wanted to ask for some help. I drive a 2007 silverado nnbs 5.3 LT 4X4 ext cab. I currently have an issue with my left turn signal not working. It starts to flash rapidly on my dashboard but no actual light outside. Also my left break light does not light up when I press on the breaks. I changed all the left side bulbs on both front and back. I changed the break switch sensor, I checked all fuses that are located on the side of the drivers dashboard. I was told to change my positive battery cable to 2ga. Also I read that I could change the turn signal flasher but when I look at th fuse box in inside the hood, I can’t find it! Will I need to replace by BCM? Idk what to do, has anyone have this issue in the past! Thanks!!

No. You are going way way out of the way here. 90% of the time it is the harness. The other 10% of the time it is the break out. But lets do some diag before we get to throwing parts at it. But before I can do that I need to know if it is a new body style 2007 or a classic.

Officialerickm · April 13, 2018

13 hours ago, carnau said:

No. You are going way way out of the way here. 90% of the time it is the harness. The other 10% of the time it is the break out. But lets do some diag before we get to throwing parts at it. But before I can do that I need to know if it is a new body style 2007 or a classic.

It is a new body style 2007. Today I bought a harness for the back left tail light and it still didn’t work. Luckaly I was able to return it! Im hoping it’s the front left harness!

Officialerickm · April 13, 2018

16 hours ago, carnau said:

No. You are going way way out of the way here. 90% of the time it is the harness. The other 10% of the time it is the break out. But lets do some diag before we get to throwing parts at it. But before I can do that I need to know if it is a new body style 2007 or a classic.

Update!!!! I changed the drivers side harness as well and still nothing!!! The fuse on the side panel of the dash keeps going out after I replace it!! I know now that there’s a short but how to find it and what to do next!

carnau · April 17, 2018

On 4/13/2018 at 2:26 AM, Officialerickm said:

Update!!!! I changed the drivers side harness as well and still nothing!!! The fuse on the side panel of the dash keeps going out after I replace it!! I know now that there’s a short but how to find it and what to do next!

Gotta trace the wire if it keeps blowing the fuse. Disconnect the wire for the distribution block and see if it keeps blowing. That will tell you what part of the harness it is in. Also make sure the distribution block is not corroded.