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Network Communication DTC Troubleshooting Index

NOTE:  Record all DTCs, and sort them by DTC type using the DTC troubleshooting index, then troubleshoot the DTC (s) in this order:

MICU 

DTC Description DTC type
B1002 MICU internal error (EEPROM error) Internal error
B1003 MICU update error Internal error
B1028 Rear wiper motor (Park) signal error Signal error
B1036 IG1 power supply circuit malfunction Signal error
B1077 Windshield wiper motor (Park) signal error Signal error
B1127 Driver's door key cylinder switch input circuit malfunction (Simultaneous input of lock and unlock signal) Signal error
B1128 Driver's door remote switch input circuit malfunction (Simultaneous input of lock and unlock signal) Signal error
B1129 Driver's door knob switch input circuit malfunction (Simultaneous input of lock and unlock signal) Signal error
B1275 Headlight OFF position circuit malfunction Signal error
B1276 Headlight switch parking (small) position circuit malfunction Signal error
B1278 Headlight ON position circuit malfunction Signal error
B1277 Head light AUTO position circuit malfunction Signal error
B1279 Dimmer switch circuit malfunction Signal error
B1280 Turn signal switch circuit malfunction Signal error
B1281 Front wiper MIST position circuit malfunction Signal error
B1282 Front wiper INT (AUTO) position circuit malfunction Signal error
B1283 Front wiper LOW position circuit malfunction Signal error
B1284 Front wiper HIGH position circuit malfunction Signal error
U1280 Communication bus line error (BUS-OFF) Loss of communication
U128D MICU lost communication with gauge control module Loss of communication

Gauge Control Module 

DTC Description DTC type
B1175 Fuel level sensor (Fuel gauge sending unit) circuit malfunction Signal error
B1176 Fuel level sensor (Fuel gauge sending unit) circuit short Signal error
U0029 F-CAN communication line error Loss of communication
U0100 Gauge control module lost communication with ENG/AT Loss of communication
U0121 Gauge control module lost communication with ABS modulator-control unit Loss of communication
U0122 Gauge control module lost communication with VSA modulator-control unit Loss of communication
U0131 Gauge control module lost communication with EPS unit Loss of communication
U0151 Gauge control module lost communication with SRS unit Loss of communication
U1280 Communication bus line error (BUS-OFF) Loss of communication
U1281 Gauge control module lost communication with MICU (MICU frame) Loss of communication
U3000-49 ECU internal circuit malfunction Internal error
U3000-51 Reprogramming error Internal error

Climate Control 

DTC Description DTC type
B121A An open in the mode control motor circuit Signal error
B121B A short in the mode control motor circuit Signal error
B121D Humidity/in-car temperature sensor communication error Signal error
B121E Electric capacity type switch IC communication error Signal error
B1220 A short in the recirculation control motor circuit Signal error
B1227 An open in the outside air temperature sensor circuit Signal error
B1228 A short in the outside air temperature sensor circuit Signal error
B1229 An open in the sunlight sensor circuit Signal error
B1230 A short in the sunlight sensor circuit Signal error
B1231 An open in the evaporator temperature sensor circuit Signal error
B1232 A short in the evaporator temperature sensor circuit Signal error
B1233 An open in the air mix control motor circuit Signal error
B1234 A short in the air mix control motor circuit Signal error
B1235 A problem in the air mix control motor circuit, linkage, door, or motor Signal error
B1240 A problem in the mode control motor circuit, linkage, door, or motor Signal error
B1241 A problem in the blower motor circuit Signal error
B2983 A problem in the recirculation control motor circuit, linkage, door, or motor Signal error
B2986 An open in the recirculation control motor circuit Signal error
U1280 Communication bus line error (BUS-OFF) Loss of communication
U128D Lost communication with gauge control module Loss of communication

Automatic Lighting Control Unit/Sensor 

DTC Description DTC type
B1575 Auto light sensor error Internal error
U1280 BUS OFF state is detected by CAN controller Loss of communication
U1281 Auto light control unit lost communication with MICU Loss of communication
U128D Auto light control unit lost communication with gauge control module Loss of communication

Immobilizer-Keyless Control Unit 

DTC Description DTC type
U1280 Communication bus line error (BUS-OFF) Loss of communication
U1281 Lost communication with MICU (MICU frame) Loss of communication
U128D Lost communication with METER Loss of communication

Keyless Access Control Unit 

DTC Description DTC type
B1601 Keyless access control unit internal (CPU) error Internal error
B1602 Keyless access control unit internal (EEPROM) error Internal error
B1632 MTR CONT signal error Signal error
B1640 RF1 antenna not connected or malfunction Signal error
B1645 Driver's door LF antenna circuit short Signal error
B1646 Driver's door LF antenna circuit open Signal error
B1647 Passenger's door LF antenna circuit short Signal error
B1648 Passenger's door LF antenna circuit open Signal error
B1657 Rear bumper LF antenna circuit short Signal error
B1658 Rear bumper LF antenna circuit open Signal error
B1659 Front interior LF antenna circuit short Signal error
DTC Description DTC type
B1660 Front interior LF antenna circuit open Signal error
B1663 Rear interior LF antenna circuit short Signal error
B1664 Rear interior LF antenna circuit open Signal error
U1280 Keyless access control unit communication bus line error (BUS-OFF) Loss of communication
U1281 Keyless access control unit lost communication with MICU Loss of communication
U128D Keyless access control unit lost communication with gauge control module Loss of communication

Keyless Access Backup Control Unit 

DTC Description DTC type
B1926 Backup control antenna open or short Internal error
B1931 Backup control unit no response Signal error
U1280 Backup control unit communication bus line error (BUS-OFF) Loss of communication
U128D Backup control unit lost communication with gauge control module Loss of communication

Keyless Access Power Control Unit 

DTC Description DTC type
B12C5 Engine start/stop switch failure Internal error
B12C6 Electric steering lock switch C/D monitor circuit failure Internal error
B12C7 Electric steering lock motor circuit failure Internal error
B12D0 Power control unit IG1A circuit error Internal error
B12D1 Power control unit IG1B circuit error Internal error
B12D2 Power control unit IG2 circuit error Internal error
B12D3 Power control unit IG latch circuit error Internal error
B12E0 Electric steering lock switch internal error Internal error
B12E1 Electric steering lock motor internal error Internal error
B12E2 Electric steering lock low level failure of MTRCUT1 Signal error
B12E3 Electric steering lock high level failure of MTRCUT1 Signal error
B12E4 Electric steering lock high level failure of MTRCUT2 Signal error
B12E5 Incorrect assembly of control unit for electric steering lock equipped vehicle Signal error
B12F0 Power control unit lost communication with electric steering lock Loss of communication
U0073 F-CAN communication bus line error Loss of communication
U0100 Power control unit lost communication with PCM Loss of communication
U0122 Power control unit lost communication with VSA modulator-control unit (VSA message) Loss of communication
U1280 Power control unit communication bus line error (BUS-OFF) Loss of communication
U1281 Power control unit lost communication with MICU Loss of communication
U128D Power control unit lost communication with gauge control module Loss of communication