Tyler Dunnam

Hello everyone I am new here, I am working on a friends early 07 (cateye) Chevy 2500 HD with the 6.0. It has a strange issue where the starter will only engage for a few seconds after the key has been turned on, after about 2 seconds the pcm removes the ground to the starter relay and the truck will not crank. If you cycle the key then the pcm will engage the starter for another 2 seconds and then stop. Also the P/N lights don’t illuminate on the dash, R/D/3/2/1 work fine. Thanks for the help everyone.