Am I crazy or what? MEP-002A AUX pump runs all the time

[1800 Diesel]

Troubleshooting update & still need sparky help!!

Kevin, sounds like either a 'stuck' relay, or a short in the wiring, but I have no great ideas where to look other than hitting the manual and tracing back and seeing what's happening. Idea: pull the DC circuit breaker and see if the pump still runs. (BTW: most of us leave the main DC breaker open when the generator is not being used...)

Fuel pumps running problem has not been solved. Have eliminated the following items (either by electrical checks per TM or swapping out part with known good):

--Battle short switch & start/stop/run switches
--Day tank float switch
--Rectifier assembly diodes (on day tank)
--DC breaker
--wiring shorts to all of the above components

Yesterday I did a short run on this unit and noticed something related to the fuel gauge that looked abnormal. With batteries connected and start/stop/run & battle short switches both off, the fuel gauge pegs to the full position when I pushed in the DC breaker. Comparing the fuel gauge operation I started another MEP-004A and observed the fuel gauge does not peg when the DC breaker is pushed in but instead the gauge slowly rises to full once the generator is up and running. (Both fuel tanks on these generators are full.)

I checked the wiring to the main fuel tank sensor and everything looked to be in order. This evening I plan to pull out the sensor assembly to see if anything is shorted or otherwise not normal. If any of you sparky types can look into this clue I would appreciate it. I'll be looking at the schematics but in that area I am still in training so it might take awhile.

Thanks in advance for any ideas. I was hoping Matt (up in the great Northwest) would weigh in, but I believe he's occupied with something as he hasn't posted in awhile.