Testing fuel pumps

[triton28]

Yesterday I was installing a pump on a 93 I am rebuilding and I thought "I should test the pump for operation before I put it in".
Now to back up a bit, I have never had the need to test a pump in the years I have been working on these. Not one failed to pump so I never had the need to test one.
So I hooked up a ground and a positive lead expecting the pump to function and got nothing. So I tried the + on another wire, and then another. Still nothing so I thought bad pump. Just to check I went to my inventory and picked out a new AfterMarket pump and got the same results. What is going on here I wondered?
The first thing I noticed was that the AfterMarket pump had different colours for 2 of the wires. The Black/Yellow and the Black were still there but the AM pump had a Red, and a Yellow in place of a Green, and a Blue as on the OEM pump. So looking at my whiz-bang schematic I noticed a difference in that the AM pump connector block had the Bk/Y connecting to the Bk/Y of the main harness as ground.
This lack of colour change for the ground connection gave me concerns so just to be sure I ran a continuity check on the Bk/Y wire coming from the AM pump, and the other 3 wires as well, from the AM pump circuitry and the Black/Yellow was indeed the ground for this AM pump, so that part made life easy: the 3 other wires of the AM pump would then be 12V+
NOTO BENE: This is NOT as per the OEM schematic colour coding as the OEM colour coding shows the BK/Y of the main harness connecting to a Green wire of the OEM pump; so remember to check whether or not the pump is OEM or AM and hook up the 12V negative from the testing battery accordingly.
So now my question was why doesn't the new pump work when I apply the 12V + feed to it. Then it hit me in a flash "The pump requires 2 of the 12V + sources to operate". This is a fail safe to ensure the pump does not pump with only the ignition on- there has to be another active 12V feed to operate. It states in the MSM that the pump won't work with just the switch ON and requires the starter button to be hit or the engine running but for some reason that didn't explain it well enough for me: that was too simply stated with no complex theory of operation. This leaves persons such as myself with a puzzled look on my face and a blank dialogue box above my head when the pump doesn't work.
So armed with this realization about requiring 2 12V feeds I connected the Red and the Yellow wire of the AM pump together, hooked up the Bk/Y ground to the battery negative and then energized the R and Y wire combo to the positive terminal and voila--pump operation.
So remember this stupid moment I had and the realizations i came to after reading the MSM 2 or 3 times, and testing the pump should be easy.
Regards,
Dave

[SgtSlag]

I own a '93. Our fuel pump died, 75 miles from our hotel, in Arkansas... They can, and do, fail. Just an FYI. Our bike currently has 75k miles on it, and at the time of the pump failure, it had around 70k miles on it. Now that it has been replaced, I doubt it will fail again, in my lifetime. Cheers!