INSTALLING PROTECTIVE LIFT PUMP RELAY
The life pump is powered through the ECM via pin #15 and #35. Every time the lift pump is energized the power drawn through the ECM causes heat. After a few thousands cycles of start/stops this heating up and cooling down cause’s degradation in the solder joints and failure. Another possible cause of ECM failure is higher than normal amperage load by either a larger capacity lift pump or a failing pump. As a lift pump starts to go bad (wear intern