Freightliner 2016 Cascadia no running lights

I have a 2016 Freightliner Cascadia my blinkers my brake lights and my emergency flashers all work okay. I do not have any tail lights. When I first turn the light switch on the tail lights will blink a few times maybe three or four seconds apart for each blink. Any ideas???

 

I will try that when I go back out to the truck thank you.

 

if I'm not mistaken the Sam chassis is the fuse box relay box under the hood on the firewall correct. Everything I see in there says trailer. Where is a relay at that is for the tail lights.

 

I turned it off for about 5 minutes turned it back on still doing the same thing.

 

No fault codes