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U0121 Diagnostic Trouble Code Discussion for March 2019

Lost Communication With EBCM

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Trouble Ticket Help Requests for DTC U0121
Help Request Posted
2007 Mazda 3 S 2.3L MIL Lamp on VIN: JM1BK32377
U0121: Communication Error To ABS-HU/CM. First off I teach High school auto mechanics so I don't see the volume of issues you guys do. I will also be the first to admit Ive not had much experience with can bus issues. Here is the issue, Custodian here at my school just bought this car off of his ...
March 29, 2019