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U0121 Diagnostic Trouble Code Discussion for June 2014

Lost Communication With EBCM


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Trouble Ticket Help Requests for DTC U0121
Help Request Posted
2004 Mazda 3 S 2.3L No Start VIN: JM1BK14314
U0121: Communication Error To ABS-HU/CM. Ok let's start over, i just closed the previous request for lack of Mazda support. Now i have support back meaning Mazda's program mmp90 is once again online. I got out codes from pcm and hec, received in codes from mazda and still nothing. As i stated in last...
June 11, 2014