My pump motor control is failing. I have a technician who is trying to fix the problem, but unfortunately, I fear we are down to buying and replacing part after part in hopes of a successful repair... On this truck, the pump motor is controlled by it's own EV1. There is a metal box under the gas pedal that houses the EV1 and various rectifiers and other components. There is neg/pos supply and neg/pos out to the pump motor. The only other wires are one ~16ga which we believe is connected to the dash light to indicate an overheat in the pump motor.

Short of trying to diagnose the problem here (the tech is still doing his best), I am wondering if there is an option for an aftermarket or more recent component that I can use to perform this function. This would be some type of pump controller that receives the full 36 volts and then divies out the voltage to the pump motor as demanded (i.e. responds to motor load by increasing voltage). The one other input I forgot to mention is a switch that forces the control to max voltage for the boom lift operation. Rather that try to dignose this antiquated (and VERY expensive due to limited part supply) old controller, it'd be great to just replace it with something more modern and reliable.

Le me know if you have any ideas! As always, thanks for your contributions!