Washer pump

Here's a wierd one, My windshield washer pump isnt working at all so I checked the voltage with a meter at the conector that plugs in the pump and I get 11-12V when I push the fluid switch. Then I take the pump out and
bench test it with 8-11V from a power supply I have and it works fine. I checked the connector and Im 100% positive that the leads are making a connection to the pump but it still doesnt work. I think that some how it is dropping the voltage when power is suplied and it detects a load, anyone know why this is happening?
thanks, Chris
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Chris C. wrote:

you have a bad or intermittent ground (on the pumps negative wire) and were grounding your meters negative lead on the car chassis, you would get a false reading. I assume your plugs connection are clean and not corroded?
Bob
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The measurements were taking from both wires (not chassis ground) and the plug connections are clean and not corroded. thanks.

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Chris C. wrote:

those two wires. The meter deals with micro amps, so the voltage drop would not be seen. When the pump is attached, the increased current across the high resistance connection would result in a voltage that is too low at the pump.
    Try to measure the voltage at the pump with the wires attached. This can be done by inserting a sewing needle into the insulation of the wires and attaching the meter to the needles. When the needles are removed, there will be no exposed wires.

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