DTC B1252-87: Communication Error With Connectivity Master Unit (CMU) (Telematics Communication Unit): Outline

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DTC B1252:87 (TELEMATICS COMMUNICATION UNIT) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with connectivity master unit (CMU)
Detection condition	The telematics communication unit cannot receive a signal from the connectivity master unit (CMU) for 5 min or more.
Fail-safe	Not applicable
Possible cause	DTCs are stored in the connectivity master unit (CMU). Connectivity master unit (CMU) connector or terminal malfunction Telematics communication unit connector or terminal malfunction Open circuit in connectivity master unit (CMU) signal circuit Telematics communication unit malfunction
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