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Home >> Infiniti >> 2012 >> M37 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 38 (Transfer Case) >> DTC/Circuit Diagnosis >> DTC P1802 - P1804, P1809: Transfer Control Unit >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

WARNING: This page is about a different car, the 2013 Nissan Xterra. However, it is still accessible from the selected car via links, so may be relevant.
DTC CONSULT Diagnostic item is detected when...
P1802 TRANSFER CONTROL UNIT  CONTROL UNIT 1 Malfunction is detected in the memory (RAM) system of transfer control unit.
P1803 TRANSFER CONTROL UNIT  CONTROL UNIT 2 Malfunction is detected in the memory (ROM) system of transfer control unit.
P1804 TRANSFER CONTROL UNIT  CONTROL UNIT 3 Malfunction is detected in the memory (EEPROM) system of transfer control unit.
P1809 TRANSFER CONTROL UNIT  CONTROL UNIT 4 AD converter system of transfer control unit is malfunctioning.