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DTC Troubleshooting Index

WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Record all DTCs, and sort them by DTC type using the DTC troubleshooting index, then troubleshoot the DTC(s) in this order:
  • Battery voltage DTCs
  • Internal error DTCs
  • Loss of communication DTCs (beginning with the lowest number first; for example, if B1005 and B1016 are retrieved, troubleshoot B1005 first).
  • Signal error DTCs

MICU 

DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1000  Communication bus line error Loss of communication
B1001  MICU internal (CPU) error Internal error
B1002  MICU internal (EEPROM) error Internal error
B1005  MICU lost communication with relay control module (RM message) Loss of communication
B1007  MICU lost communication with combination switch control unit (HLSW message) Loss of communication
B1011  MICU lost communication with gauge control module (VSP/NE message) Loss of communication
B1012  MICU lost communication with the rear fuse/relay box (RJC message) Loss of communication
B1013  MICU lost communication with driver's MPCS unit (ASLOCKSW message) _ Loss of communication
B1015  MICU lost communication with driver's MPCS unit (DRLOCKSW message) Loss of communication
B1032  MICU lost communication with the SRS unit (CDS message) Signal error
B1575 Automatic lighting sensor circuit malfunction Signal error

Relay Control Module 

RELAY CONTROL MODULE - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1050  Communication bus line error Loss of communication
B1051 Relay control module internal (CPU) error Internal error
B1052 Relay control module internal (EEPROM) error Internal error
B1055 Relay control module lost communication with MICU (MICU message) Loss of communication
B1056 Relay control module lost communication with MICU (ALARM message) Loss of communication
B1057 Relay control module lost communication with MICU (DOORSW message) Loss of communication
B1060 Relay control module lost communication with gauge control module (VSP/NE message) Loss of communication
B1061 Relay control module lost communication with gauge control module (A/T message) Loss of communication
B1062 Relay control module lost communication with combination switch control unit (HLSW message) Loss of communication
B1063 Relay control module lost communication with combination switch control unit (WIPSW message) Loss of communication
B1065 Relay control module lost communication with driver's MPCS unit (DRLOCKSW message) Loss of communication
B1075 Headlight switch back-up circuit malfunction Signal error
B1076 Windshield wiper switch back-up circuit malfunction Signal error
B1077 Windshield wiper (As) auto switch circuit malfunction Signal error
B1078 Daytime running lights system error (Canada) Loss of communication
B1079 Daytime running lights system error (USA) Loss of communication
B1080  Power supply circuit (IG1 line) input error for relay control module and MICU Signal error

Gauge Control Module 

GAUGE CONTROL MODULE - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1150  Communication bus line error Loss of communication
B1152 Gauge control module internal (EEPROM) error Internal error
B1155 Gauge control module lost communication with combination switch control unit (HLSW message) Loss of communication
B1156 Gauge control module lost communication with combination switch control unit (WIPSW message) Loss of communication
B1157 Gauge control module lost communication with MICU (MICU message) Loss of communication
B1158 Gauge control module lost communication with relay control module (RM message) Loss of communication
B1159 Gauge control module lost communication with MICU (DOORSW message) Loss of communication
B1162 Gauge control module lost communication with Power tailgate control unit (PTG message) Loss of communication
B1168 Gauge control module lost communication with PCM (ENG messages) Loss of communication
B1169 Gauge control module lost communication with PCM (A/T messages) Loss of communication
B1170 Gauge control module lost communication with VSA modulator-control unit (VSA message) Loss of communication
B1173 Gauge control module lost communication with TPMS control unit (TPMS message) Loss of communication
B1175 Fuel level sensor (fuel gauge sending unit) circuit open Signal error
B1176 Fuel level sensor (fuel gauge sending unit) circuit short Signal error
B1177 Battery voltage abnormal Battery voltage
B1178 F-CAN communication line error Loss of communication
B1180 Gauge control module lost communication with MICU (AUTOLT message) Loss of communication
B1182 Gauge control module lost communication with driver's MPCS unit (DRLOCKSW message) Loss of communication
B1187 Gauge control module lost communication with SRS unit (SRS message) Loss of communication
B1188 Gauge control module lost communication with the MICU (RM message) Loss of communication
B1189 Gauge control module lost communication with active damper system control unit (ADS message) Loss of communication

Climate Control Unit 

CLIMATE CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1200  Communication bus line error Loss of communication
B1202 Climate control unit internal error Internal error
B1205 Climate control unit lost communication with gauge control module (VSP/NE massage) Loss of communication
B1206 Climate control unit lost communication with gauge control module (ECT massage) Loss of communication
B1207 Climate control unit lost communication with gauge control module (ILLUMI massage) Loss of communication
B1213 An open in the rear evaporator temperature sensor circuit Signal error
B1214 An open in the rear evaporator temperature sensor circuit Signal error
B1215 An open in the recirculation control motor circuit Signal error
B1223 A problem in the rear blower motor circuit Signal error
B1225 An open in the in-car temperature circuit Signal error
B1226 A short in the in-car temperature sensor 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 driver's air mix control motor circuit Signal error
B1234 A short in the driver's air mix control motor circuit Signal error
B1235 A problem in the driver's air mix control linkage, door, motor or motor circuit Signal error
B1236 An open in the passenger's air mix control motor circuit Signal error
B1237 A short in the passenger's air mix control motor circuit Signal error
B1238 A problem in the passenger's air mix control linkage, door, motor or motor circuit Signal error
B1239 An open or short in the mode control motor circuit Signal error
B1240 A problem in the mode control linkage, doors, motor, or motor circuit Signal error
B1241 A problem in the blower motor circuit Signal error

Climate Control Unit 

CLIMATE CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1244 An open in the rear air mix control motor circuit Signal error
B1245 An short in the rear air mix control motor circuit Signal error
B1246 A problem in the rear air mix control linkage, door, motor, or motor circuit Signal error
B2965 Climate control unit lost communication with rear climate control panel Loss of communication
B2967 An open in the humidity sensor circuit Signal error
B2968 A short in the humidity sensor circuit Signal error
B2969 Climate control unit lost communication with gauge control module (WIPSW message) Loss of communication
B2970 Climate control unit lost communication with gauge control module (RM message) Loss of communication
B2979 An open in the A/C pressure sensor circuit Signal error
B2980 A short in the A/C pressure sensor circuit Signal error
B2981 Climate control unit lost communication with navigation unit Loss of communication
B2983 A problem in the recirculation control linkage, door, motor, or motor circuit Signal error
B2991 Climate control unit lost communication with audio unit Loss of communication

Combination Switch Control Unit 

COMBINATION SWITCH CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1250  Communication bus line error Loss of communication
B1252 Combination switch control unit internal (EEPROM) error Internal error
B1255 Combination switch control unit lost communication with MICU Loss of communication
B1275 Combination light switch OFF position circuit malfunction Signal error
B1276 Combination light switch parking (SMALL) position circuit malfunction Signal error
B1277 Headlight switch AUTO position circuit malfunction Signal error
B1278 Headlight switch ON position circuit malfunction Signal error
B1279 Headlight switch DIMMER position circuit malfunction Signal error
B1280 Turn signal switch circuit malfunction Signal error
B1281 Windshield wiper switch MIST position circuit malfunction Signal error
B1282 Windshield wiper switch INT position circuit malfunction Signal error
B1283 Windshield wiper switch LOW position circuit malfunction Signal error
B1284 Windshield wiper switch HIGH position circuit malfunction Signal error

Power Tailgate Control Unit 

POWER TAILGATE CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1350  Communication bus line error Loss of communication
B1352 Power tailgate control unit internal (EEPROM) error Internal error
B1355 Power tailgate control unit lost communication with MICU (MICU message) Loss of communication
B1356 Power tailgate control unit lost communication with driver's MPCS unit (DRLOCKSW message) Loss of communication
B1357 Power tailgate control unit lost communication with gauge control module (VSP/NE message) Loss of communication
B1358 Power tailgate control unit lost communication with driver's MPCS unit (ASLOCKSW message) Loss of communication
B1359 Power tailgate control unit lost communication with gauge control module (A/T message) Loss of communication
B1375 Driver's door power tailgate switch circuit malfunction Signal error
B1376 Power tailgate outer handle switch circuit malfunction Signal error
B1377 Inside tailgate switch circuit malfunction Signal error
B1378 Power tailgate right pinch sensor circuit malfunction Signal error
B1379 Power tailgate left pinch sensor circuit malfunction Signal error
B1380 Tailgate closer unit open switch circuit malfunction Signal error
B1381 Tailgate closer unit close switch circuit malfunction Signal error
B1382 Tailgate closer unit full latch switch circuit malfunction Signal error.
B1383 Tailgate closer unit ratchet switch circuit malfunction Signal error
B1384 Tailgate closer unit half latch switch circuit malfunction Signal error
B1386 Power tailgate sensor pulse A circuit malfunction Signal error
B1387 Power tailgate sensor pulse B circuit malfunction Signal error
B1388 Power tailgate motor circuit malfunction Signal error
B1389 Power tailgate motor clutch circuit malfunction Signal error
B1390 Power tailgate closer function error Signal error

Hands Free Link Control Unit 

HANDS FREE LINK CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1750  Communication bus line error Loss of communication
B1775 Microphone input/output short to power/open Signal error
B1776 Microphone input/output short to ground/open Signal error
B1779 HFL switch or HFL-voice control switch (HFL talk/ HFL back buttons) circuit open/short Signal error
B1780 HFL-voice control switch (HFL talk/HFL back buttons) circuit short Signal error
B1785 Incorrect configuration (VEHINFO Frame) Signal error
B1786 HandsFreeLink control unit lost communication with gauge control module (VEHINFO Frame) Signal error
B1792 HandsFreeLink control unit internal error Internal error

Immobilizer-Keyless Control Unit 

IMMOBILIZER-KEYLESS CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1900  Communication bus line error Loss of communication
B1905 Immobilizer-keyless control unit lost communication with driver's MPCS unit (DRLOCKSW message) Signal error
B1906 Immobilizer-keyless control unit lost communication with gauge control module (A/T message) Signal error

Rear MICU 

REAR MICU - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1950  Communication bus line error Loss of communication
B1955 Rear MICU lost communication with MICU (MICU message) Loss of communication
B1956 Rear MICU lost communication with gauge control module (A/T message) Loss of communication
B1957 Rear MICU lost communication with combination switch control unit (HLSW message) Loss of communication
B1958 Rear MICU lost communication with combination switch control unit (WIPSW message) Loss of communication
B1959 Rear MICU lost communication with relay control module (RM message) Loss of communication

Power Seat Control Unit 

POWER SEAT CONTROL UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B1800  Communication bus line error Loss of communication
B1802 Power seat control unit internal (EEPROM) error Internal error
B1805 Power seat control unit lost communication with gauge control module (VSP/NE message) Loss of communication
B1806 Power seat control unit lost communication with MICU (MICU message) Loss of communication
B1808 Power seat control unit lost communication with gauge control module (A/T message) Loss of communication
B1810 Power seat control unit lost communication with MICU (MIRRORSW message) Loss of communication
B1811 Power seat control unit lost communication with MICU (DOORSW message) Loss of communication
B1812 Power seat control unit lost communication with driver's MPCS unit (MEMSW message) Loss of communication
B1825 Power seat slide motor pulse error Signal error
B1826 Power seat front up-down motor pulse error Signal error
B1827 Power seat rear up-down motor pulse error Signal error
B1828 Power seat recline motor pulse error Signal error
B1829 A/T P signal and VSS signal mismatch Signal error
B1835 Tilt/telescopic switch signal input error Signal error
B1836 Power seat position sensor circuit short Signal error
B1837 Driving position memory recall timeout Signal error
B1840 Tilt motor pulse error Signal error
B1841 Telescopic motor pulse error Signal error
B1842 Power tilt/telescopic position sensor power supply circuit (SVCC line) short Signal error
B1843 Power seat control unit lost communication with power tilt/telescopic steering control unit (UART line) Signal error
B1844 Power seat slide switch circuit malfunction Signal error
B1845 Power seat recline switch circuit malfunction Signal error
B1846 Power seat front up-down switch circuit malfunction Signal error
B1847 Power seat rear up-down switch circuit malfunction Signal error

Driver's MPCS Unit 

DRIVER'S MPCS UNIT - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B2150  Communication bus line error Loss of communication
B2152  Driver's MPCS unit internal (EEPROM) error Internal error
B2155  Driver's MPCS unit lost communication with MICU (MICU message) Loss of communication
B2156  Driver's MPCS unit lost communication with MICU (MIRRORSW message) Loss of communication
B2157  Driver's MPCS unit lost communication with gauge control module (ILLUMI message) Loss of communication
B2160  Driver's MPCS unit lost communication with gauge control module (VSP/NE message) Loss of communication
B2161  Driver's MPCS unit lost communication with MICU (DOORSW message) Loss of communication
B2162  Driver's MPCS unit lost communication with relay control module (RM message) Loss of communication
B2175 Driver's window motor pulse A error Signal error
B2176 Driver's window motor pulse B error Signal error
B2177 Front passenger's window motor pulse A error Signal error
B2178 Front passenger's window motor pulse B error Signal error
B2179 Driver's door key cylinder switch LOCK/UNLOCK signal error Signal error
B2180 Driver's door lock switch LOCK/UNLOCK signal error Signal error
B2181 Driver's door lock knob switch LOCK/UNLOCK signal error Signal error
B2182 Left power mirror horizontal sensor signal error Signal error
B2183 Left power mirror vertical sensor signal error Signal error
B2184 Right power mirror horizontal sensor signal error Signal error
B2185 Right power mirror vertical sensor signal error Signal error
B2186 Front passenger's door lock switch LOCK/UNLOCK signal error Signal error
B2187 Communication line (UART line) communication error (Driver's MPCS unit from Driver's MPCS unit) Signal error
B2188 Communication line (UART line) circuit open Signal error
B2189 Driver's window position detect circuit error Signal error
B2190 Front passenger's window position detect circuit error Signal error
B2191 Front passenger's MPCS unit internal (EEPROM) error Internal error

AcuraLink Control Unit 

AcuraLink Control Unit - DTC TROUBLESHOOTING CHART

DTC Description DTC Type
B2200  Communication bus line error Loss of communication
B2202 AcuraLink control unit EEPROM error Loss of communication
B2204 B-CAN communication line error Loss of communication
B2205 F-CAN communication line error Loss of communication
B2207 Navigation unit control unit lost communication with AcuraLink control unit Loss of communication
B2208 HandsFreeLink control unit lost communication with AcuraLink control unit Loss of communication
B2209 AcuraLink control unit internal error Loss of communication
B2240 XM antenna error Signal error