09 Silvy Left Brake Light/Turn Signal In-op

15SilvyHC · January 16, 2018

2009 Silverado and neither the brake nor turn signal lights are working on the taillight of the drivers side. I have tried changing bulbs to no avail. I have also checked fuses (all good) and inspected wiring to the best of my ability (no noticeable damage). Turn signals on headlamp work but hyperflash. Any other common areas of failure that might cause this? A switch or some type of relay etc somewhere? Any input is appreciated.

carnau · January 17, 2018

More than likely it is the harnesses. But lets do a little checking. Go to the rear junction block for the tail lights (under the bed of the truck). You will have a harness coming into it from the main harness and then 2 harnesses leaving for the tail lights. (you can click on the junction block below and see what it looks like)

Check the Yellow wire using a test light with the left turn signal on coming into the junction block. Connector 1 terminal A. If your test light is blinking power is getting to the rear of the truck.

If it is blinking remove Connector 2 and check the male lead at terminal H of the Junction block and see if it is blinking. If it is your tail light harness is bad. If it is not your junction block is bad.

Left tail lamp harness - http://amzn.to/2FIobNx

Right tail lamp harness - http://amzn.to/2reWSXT

Junction Block - http://amzn.to/2DETBUu

15SilvyHC · January 17, 2018

12 hours ago, carnau said:

More than likely it is the harnesses. But lets do a little checking. Go to the rear junction block for the tail lights (under the bed of the truck). You will have a harness coming into it from the main harness and then 2 harnesses leaving for the tail lights. (you can click on the junction block below and see what it looks like)

Check the Yellow wire using a test light with the left turn signal on coming into the junction block. Connector 1 terminal A. If your test light is blinking power is getting to the rear of the truck.

If it is blinking remove Connector 2 and check the male lead at terminal H of the Junction block and see if it is blinking. If it is your tail light harness is bad. If it is not your junction block is bad.

Left tail lamp harness - http://amzn.to/2FIobNx

Right tail lamp harness - http://amzn.to/2reWSXT

Junction Block - http://amzn.to/2DETBUu

I didn't get the chance to check this out yesterday will be doing it today. Thanks for the info!!

15SilvyHC · January 17, 2018

Ended up being the junction box. Swapped out and back in business! Actually don't even know if old one was bad. Had some corrosion or crap on one of the pins might have been issue. Just changed out while i was at it.

Thanks for the pro tips!

Sent from my Pixel XL using Tapatalk

carnau · January 17, 2018

3 hours ago, 03pewterZ said:

Ended up being the junction box. Swapped out and back in business! Actually don't even know if old one was bad. Had some corrosion or crap on one of the pins might have been issue. Just changed out while i was at it.

Thanks for the pro tips!

Sent from my Pixel XL using Tapatalk

Glad you got it fixed! =-)