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Home >> Infiniti >> 2016 >> QX80 Base, RWD >> Repair and Diagnosis (Single Page) >> Transmission >> Transfer Case >> Transfer Case (DTC/Circuit Diagnosis) >> Circuit Diagnosis >> DTC P1802, P1803, P1804, P1809: Transfer Control Unit >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

DTC Display item Malfunction detected condition Possible cause
P1802 CONTROL UNIT 1 Malfunction is detected in the memory (RAM) system of transfer control unit. Internal malfunction of transfer control unit.
P1803 CONTROL UNIT 2 Malfunction is detected in the memory (ROM) system of transfer control unit.
P1804 CONTROL UNIT 3 Malfunction is detected in the memory (EEPROM) system of transfer control unit.
P1809 CONTROL UNIT 4 AD converter system of transfer control unit is malfunctioning.