93 Chevy PU code 54

After I finally decided that the fuel pump was bad and replaced it the service engine soon came on with a code 54 (fuel pump voltage not present at fuel pump sense line for 2 seconds after the ECM has sent the fuel pump on command. Low voltage) this was not there before I replaced the fuel pump. Have tried clearing codes but sets it immediately. Truck seems to run okay-I little longer starting. Any suggestions on how to diagnois this would be greatly appreciated. 1993 Chevy K1500, 350 engine.
Thanks.

After I finally decided that the fuel pump was bad and replaced it the service engine soon came on with a code 54 (fuel pump voltage not present at fuel pump sense line for 2 seconds after the ECM has sent the fuel pump on command. Low voltage) this was not there before I replaced the fuel pump. Have tried clearing codes but sets it immediately. Truck seems to run okay-I little longer starting. Any suggestions on how to diagnois this would be greatly appreciated. 1993 Chevy K1500, 350 engine.
Thanks.
Replace the fuel pump relay

Replace the fuel pump relay


Thanks! That seemed to take care of it.