Welcome to the Caterpillar ECM repair page. Caterpillar ECMs are tough. They never went to the thin laminate circuit paper like everyone else. Cat ECMs use ridged circuit boards that can be completely removed from the ECM case....but some of the circuit board components are glued to the case with epoxy and cannot be easily removed. I don't pull the circuit board in these ECMs unless I'm fairly certain I am going to find something. Please click one of the three links above to proceed.