There is a number of things we have to consider before starting the diagnosis. First, if you were measuring that 6 volts at the fuel pump's connector with it unplugged, that may be confusing the real cause of the problem. This would be similar to standing on a garden hose and blocking ninety nine percent of it. You would still see full pressure at the nozzle, as long as it was closed. No water is flowing, so no pressure is dropped across your foot. Voltage is electrical pressure. With the connector unplugged, no current is flowing, so no electrical pressure, (voltage), is dropped across some undesirable resistance in the circuit.
The ignition switch does not need to be on for this. The jumper will energize the circuit, and the fuel pump should be running. If it is, this entire part of the circuit is okay. If it is not running, now is the time to work your way through the circuit with the test light.
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May 29, 2021 at 11:03 AM
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