My pump runs when the key is in the on position (engine not started) and in the accessory position.
Is this correct?
CStockton since you added the FASS set up to your truck with the TST PMCR have you tried using your A/C for any time and did it cool ok?
I dont know what the deal is but I recently added the FASS and my A/c stopped working properly, I spoke to Mark at TST yesterday and he was familiar with the problem and had me relocate the ground wire from the battery to a ground under the dash and that took care of issue. Sounds strange but apparently going from a Direct ground to a secondary ground did it.
OR you could get a relay and use the hot wire back at the tank (Pin #4) to trigger the relay. This would do the same thing more or less.
What type of relay would I need?