Forgot to post my last reply until just now! So I re-installed the V1.1.4, loaded the original SD card files that came with the E3Pro, placed into the printer. Turned it on and auto home seemed ok. Noted the the display immediately showed 354 at the nozzle and 25 on the bed. Set my normal temps of 215 and 63 and in 2 or 3 seconds a message of 'HIGH TEMP, RESET' came up. Tried a couple more times with same results, so obviously something is amiss, although I couldn't detect any heat in the nozzle. Went ahead and leveled the bed COLD so I could check auto home and it appeared to be correct! I'm reassured by this tiny positive result but still have no idea why the 4.2.7 is askance or the anomaly in the nozzle circuit exists.