You have an electric 12V DC motor and a vane pump. Usually they will have at some Ohms through the carbon brushes. Perhaps you had the scale set too high?
The right way to test it is with disassembly and a growler but that doesn't tell you the conditions of the pump.
If further disassembly doesn't reveal anything abnormal I'd prolly feel safe enough to run it as is unless it's critical, then I'd replace it.