I have a 2017 silverado Z71 my rear passenger tail lamps are out and I cant figure it out!
Here's what I've tried pulled the bulbs check them they are good bought all data for a month and got some info there on wires pins fuses etc checked the ground wire at the tail light its good checked power found the problem here as it only has 0.5v the driver side has 12v dropped the spare tire and unplugged the harness i power probed it and made the lights work. checked the power on harness to bcm still 0.5v also good ground. unplugged X4 connecter on the bcm gave power to wire # 4 and lights worked. I also checked fuse 28 and relay 63 under the hood they are fine. and i checked fuse 45 'bcm6' on passenger side fuse block also good. I checked ground 121 also good. I cant figure it out could my bcm be bad? I have a modis scanner but it needs an update so i cant see history codes the light is not on the dash so no current codes i assume. really don't want to update the scanner yet either might not even help me anyways with this.

 

I should say it is just the right rear running lamp is out

 

I used my scanner under 2016 and was able to see there is no codes, I was able to use the funtions and switch on drv side lights as they work but when I switch on pass side the front light works but no rear still.