2006 Kenworth, engine cranks does not start, have the three B+ at pins 48, 52, and 53 B- at 63, 65, and 67 good, also have the ignition B+ at pin 70. Engine ECM cannot be communicated with via my scanner. Key on, the solenoid for the air controlled fan clutch cycles on and off. The data link tests good at 60 ohms. Found an extremely poor battery negative connection at the starter, so bad that the engine stopped cranking at all until it was repaired. Had this exact no start one month ago, disconnected the two harness plugs from the ECM, plugged them back in and the engine started.