I changed both batteries on my 2004 Dodge Ram 2500 Diesel Cummins and now my electric fuel pump relay repeatedly clicks and the engine won't start. The fuel pump was retrofitted by the dealer approximately 8 months ago to an electric fuel pump. I bought an obd-II scanner and it wouldn't communicate with the truck computer. Help!

Bought a new relay-acts the same, the clicking has a steady tempo and the engine light with the fuel light also stays on when the ignition switch is on-truck has two batteries with redundant grounds to chassis and frame-lights and other things work fine in the truck. Relay fuse good. Scanner support help-line told me the truck had to be running first for the scanner to work and diagnose codes. The scanner communicated with my wifes car no problem. Could changing the batteries have blown my pcm-how could I tell if that happened? Is there a way to reset a pcm-left negatives off battery overnight with no change in condition. Bought a new relay-acts the same, the clicking has a steady tempo and the engine light with the fuel light also stays on when the ignition switch is on-truck has two batteries with redundant grounds to chassis and frame-lights and other things work fine in the truck. Relay fuse good. Scanner support help-line told me the truck had to be running first for the scanner to work and diagnose codes. The scanner communicated with my wifes car no problem. Could changing the batteries have blown my pcm-how could I tell if that happened? Is there a way to reset a pcm-left negatives off battery overnight with no change in condition.