2013 Chevy 3500 fuel pump and sending unit replacement gas gauge is not working right

[Lg1986]

Replaced both fuel pumps and sending units in the tanks now the gas gauge is not working right. Any ideas?

 

[davester]

Didn't put the float on the arm in the tank, connectors damaged or not fully inserted, wiring problem, incorrect pump installed, faulty pump installed.

 

Maybe describe how it is not working right?

[Lg1986]

Turn the key on the truck starts the gauge goes about halfway then goes completely down to empty .on the front and rear tank put new fuel pumps and sending units in matched up the VIN number have the right parts everything.

[davester]

Is that movement part of the initial gauge test sweep, or after that?

 

Anyway, only thing I can suggest is using a scanner to see if the problem is before the bcm or after by reading what the computer thinks the fuel levels are.  But most likely, assuming the system was working before the old pumps failed, that the problem is before the bcm, perhaps a fuse blew, or it's a problem at the pumps themselves (bad sender, or connector/wiring problem there).