M6604 bobcat code. The M6604 code indicates no communication with the ECU, often due to faulty wiring harnesses, loose battery terminals, or damaged connectors. The Bobcat Machine Diagnostics & Fault Codes search tool is designed to identify the type of fault code displayed by your Bobcat machinery and the next steps needed to resolve the diagnostic or fault code. First select your vehicle and then find the fault code in that page. Any help or ideas would be great. Code M6604 on a Bobcat T750 indicates an engine start circuit fault. Saying no power to the ECU I have switched all the relays found no change, fuses are all good but did notice I Diagnostic service codes for Bobcat vehicles can be either letters or numbers, before check them please select your Bobcat construction vehicle below. Code M6604 on the Bobcat T740 typically indicates a fuel system fault. Check battery terminals for tight, clean connections and sufficient voltage. Begin by checking the engine control unit connections and battery voltage. They don’t always come on at the same time but most of the time they do. qo84 q2d8zy gwm 2fqb gn0 a2x s1gi ejqsam3 i9veul8 41