I have a TAC50 that randomly shuts down on a Door Comm loss fault 1103, I have changed door board and Car node in COP. The car may run 10min up to 2 hours, check my resistance on CH/CL and have 60ohms. The shut always happens when door closes and ready to run

Make sure the door software is V2R23, comm is plugged into Con3 not Con7 & JP5 is off. If you have 60 ohms then the termination resistors/ jumpers are off as they should be. CCH should be about 2.5 vdc to ground and CCL should be slightly lower like 2.4. If those are off the most likely cause is the CPU, if they are good I would try to use a spare shielded cable in the traveler. Also, If any of the plugs are not screw terminals make sure the spring connection is not on the insulation.

Well my door operator software is V2R11( but it came off car that was running across the hall)spent most of day checking wiring, resistance equals 60 ohms, Changing conductors, etc.

Still no progress, all boards except Micro have been replaced.

Replace it in AM