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P911sc, regarding the troubleshooting of the fuel pump and circuit, remember that just because you apply power to the fuel pump, it still needs a path to ground. So prior to replacing the pump assure it has an adequate ground. You may want to use a dvom and on the ohms part of the meter see if the internals of the pump have an open circuit. I'm not sure where this pump is located but if you can sometimes tap on the pump and see if it responds.
Regarding the fuel pump relays wiring:
#30 is 12v all the time.
#87 is wire to fuel pump.
#15 is 12v with key on.
#31 is the ground.
#31b is the magic little terminal that keeps everyone safe. This terminal goes to the distributor, or point, side of ignition coil. It provides the "signal" to the fuel pump relay that the engine is running, or cranking over. This is the "built in" safety feature as the manufacturer did not want the fuel pump running with out the engine running. Worst case scenario would be a ruptured fuel line oe car wreck and the pump is pumping gas onto the motor. So basically 31b is the tach signal to the fuel pump relay. VW has used this type of relay since 1975, on its water cooled cars.
Got it. Hope this helps, Bill
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