Ive got a 2000 Blazer 4D. Fuel pump went out. Bought new fuel pump. Replaced fuel filter, relay switch and connector harness for pump. Tested with meter voltage on the wires that connect to pump connector. Have power. Hooked up pump to battery, pump works. Completely dropped tank and replaced the pump. Now can not get power to the pump. Don't even hear it turn on when I turn ignition on. Removed everything, checked the wires once again, the pump, etc. Put back together, still nothing. Any ideas, Im at my wits end???

 

could be faulty relay, even new ones are crap outta the box. is your security light on? the factory security system is problematic. sadly, the ignition and fuel pump both shut down when the alarm is "set off" try this. turn key to on, without starting, leave it sit like that for 15 minutes, then turn it off for 15 seconds. then try to start. if that doesn't work, check fuses. under hood and under dash.

 

checked relay switch, its fine. tried the security trick as well. all the fuses are ok as well. literally everything works up until you plug in the connector into the fuel pump. then nothing.

 

fuel pump SHOULD have come with a new wire harness. was that replaced?

 

In the process of dropping the tank and connecting and disconnecting the wires something must have happened to the wires. Closely inspect the wires for breaks or bad spots. Anew harness would be great if you have one.

 

yes, i replaced the harness. really starting to think there is a short in the ground somewhere. any idea how difficult it would be to pull the wires?

 

you may be right about the wires. we've used 2 new harnesses.