Computer code 543

I have a 1994 5.0 and my 02 sensors were bad so i replaced them then i scanned the computer to see if the bank 1 and 2 lean codes were gone, and they were. However, while running the engine on test i got engine code 543 which basically says there is an open connection between the fuel pump and the battery. Thing that is really pissing me off is I didnt touch anything else. I jacked up the car, replaced the sensors, put the car down, ran the test. Does part of the fuel pump relay run through the O2s? I checked all the fuses in the engine compartment fuel box and they all came out fine. The even weirder thing is the car started at first and ran then gave me the code and then it wouldnt start.

Any suggestions at all? Otherwise I guess I have to get it towed to an electrical shop.

edit - I read the 543 diagnostics write up, I will try putting in one of the old o2 sensors on the left side.

I tried replacing the left O2 sensor and I checked out the pins on both male and female connectors several times... I dont see anything wrong. I guess I will have to try to trace the wires all the way up.

Wystang how would I go about clearing the codes? I don't have an aftermarket tuner, I just have an EEC reader. Do you mean just reseting the computer?

Right now the fuel pump will not come on at all. I turn the key forward and get nothing (no hum)

I guess I will end up taking the wrapping off the trail of wires that snakes up the front of the engine and looking for something torn or shorting