People are stupid. Buy a used rack for $30 and spend the hour or less of your not so precious time to fix it. If not, then try switching the battery terminals to check for codes in case your ecu can tell you something.
Just when you remove the cover in the trunk, pick out the ground wire in the clump, and ground it to the chassis. Mine was thinning and eventually cut itself so that's when I grounded it to the chassis.
Just snip the ground wire on top of the pump and ground it to one of the 4 holes on the tan cover in the trunk. I've been running mine like that for a year now with no problems. I Think that's what fixed my problem.
Come to think of it, one day I was messing around in there, the ground wire came off the little plug above the pump, and ever since I re-did it, it's been perfect. So check for a bad ground I guess.