DTC U2638-16: Light Control Module (RH) Power Supply Circuit (B2+) Malfunction (BCM) (Us): Outline

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DTC U2638:16 (BCM) (US) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Light control module (RH) power supply circuit (B2+) malfunction
Detection condition	The light control module (RH) (built into front combination light (RH)) power supply circuit (B2+) voltage is lower than the standard.
Fail-safe	Not applicable
Possible cause	DTCs are stored in the PCM. Battery malfunction Malfunction in generator Front combination light (RH) connector or terminal malfunction Short to ground or open circuit in front combination light (RH) power supply circuit (B2+) Front combination light (RH) internal malfunction Body control module (BCM) malfunction
Courtesy of MAZDA MOTORS CORP.