| Believe me. I know how this works. Look these pictures over carefully. There is no ground at all to the FPC until it is grounded. There is a shield wire coming out of the FPC that goes to the fuel pump and that wire is only a shield. It connects to ground when the FPC chassis is grounded to the car body (see the FPC circuit picture). It is only connected to the shield of the wire that controls the fuel pump ground (see the schematic picture). I hi-lited the shield wire in red in the schematic. The fuel pump motor wire (or MO) is a controlled ground. It only works properly if the FPC circuit is grounded via the FPC chassis grounded to car body ground. Otherwise the ground is a potential ground created by the circuit. The fuel pump motor may attempt to run or even run to a certain extent but it will not run correctly. There will be no speed control. It can run and make you think it's working OK but in reality it's not. So as you can see, there is no ground at the FPC until its chassis is grounded to the car body. I just helped someone a few weeks ago who's car would not start. He was trying everything and was able to get the fuel pump to work by by-passing the FPC. When the FPC connector was connected it would only kick the fuel pump for 2 or 3 seconds whenever he tried to start the car. I asked him if the FPC was bolted in place and he said no, it was just sitting there. After he bolted it back in place his car ran fine. Again, you may have been able to run a car without it bolted to the car body but it was only because that circuit had a more ground potential than this guy's did. It still wasn't working correctly and there was no speed control. 
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