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Under-Dash Fuse/Relay Box

Fig 1: Under-Dash Fuse/Relay Box Replacement Components
GHH464694Courtesy of HONDA, U.S.A., INC.
Under-Dash Fuse/Relay Box Legend

Fuse Number Amps Component(s) or Circuit(s) Protected Feature
B1 --- Not used  
B2 15 A Brake light relay*,
CMP sensor A,
Electrical load detector (ELD),
EVAP canister purge valve,
MAF sensor,
PCM (BKSWNC) (via brake pedal position switch),
Secondary HO2S (sensor 2)		 *: With CMBS
B3 10 A SRS unit  
B4 15 A Electric steering lock*,
Fuel pump (via PGM-FI main relay 2),
Keyless access/TPMS control unit,
PCM (IG1 (FUEL PUMP))		 *: Mexico models
B5 7.5 A A/T gear position indicator,
CAN gateway*1,
Gauge control module,
MICU (IG1 METER),
Reverse relay circuit (built into the under-dash fuse/relay box),
Shift lock solenoid,		 *1:'19-21*
2: Without touch screen
*3: Without navigation
*4: With navigation
*5: With automatic dimming inside mirror
Via reverse relay circuit (built into the under-dash fuse/relay box):
Audio display unit*2,
Audio unit*3,
Audio-navigation unit*4,
Automatic dimming inside mirror*5,
Back-up lights,
MICU (BACK LT)
B6 7.5 A ANC/active sound control unit,
Left side BSI radar unit*1,
Millimeter wave radar*2,
Multipurpose camera unit*2,
Multipurpose camera unit (via RDM switch)*2,
Power seat control unit*3,
RDM switch indicator*2,
Right side BSI radar unit*1,
Starter cut relay 1,
Starter cut relay 2,
Telematics control unit*4*5,
Windshield washer motor relay,
Windshield wiper main relay		 *1: With blind spot information system/cross traffic monitor
*2: With LKAS/ACC/CMBS
*3: With DPMS
*4: USA and Canada models
*5: With navigation
B7 7.5 A PCM (IG MISS SOL)  
B8 15 A Front passenger's door lock actuator, Right rear door lock actuator  
B9 15 A Left rear door lock actuator  
B10 15 A Audio unit*1,
Audio-navigation unit*2,
CarPlay and Android Auto unit*3*4		 *1: Without navigation
*2: With navigation
*3: With touch screen
*4:'19-21
B11 20 A Moonroof motor-control unit  
B12 20 A Power seat control unit*2 *1: Without DPMS
*2: With DPMS
Via driver's power seat adjustment switch*1:
Driver's power seat front up-down motor,
Driver's power seat rear up-down motor,
Driver's power seat recline motor,
Driver's power seat slide motor
B13 20 A Driver's power seat adjustment switch*1,
Power seat control unit*2		 *1: Without DPMS
*2: With DPMS
B14*1 15 A*2
20 A*3		 Driver's seat heater relay (high),
Driver's seat heater relay (low),
Front passenger's seat heater relay (high),
Front passenger's seat heater relay (low)		 *1: With seat heater
*2: '17-18
*3: '19-21
Via driver's seat heater relays:
Driver's seat-back heater,
Driver's seat cushion heater
Via front passenger's seat heater relays:
Front passenger's seat-back heater,
Front passenger's seat cushion heater
B15 10 A Driver's door lock actuator  
B16* 20 A Front passenger's power seat slide motor (via front passenger's power seat adjustment switch) *: With front passenger's power seat
B17* 20 A Front passenger's power seat recline motor (via front passenger's power seat adjustment switch) *: With front passenger's power seat
B18* 10 A Power lumbar support motor (via power lumbar support switch) *: '19-21
B19 7.5 A A/T gear position indicator,
Audio unit*1,
Audio-navigation unit*2,
Center display unit*4,
Center switch panel/interface dial*4,
Console accessory power socket relay,
HFL-ANC/active sound control microphone*3,
Telematics control unit*2*5		 *1: Without navigation
*2: With navigation
*3: Without touch screen
*4: With touch screen
*5: USA and Canada models
B20 7.5 A Not used  
B21 7.5 A Not used  
B22 7.5 A Automatic dimming inside mirror*1,
A/C compressor clutch relay,
Blower motor relay,
Climate control unit,
Driver's seat heater switch*2,
Front passenger's seat heater switch*2,
HVAC display unit*3,
Power mirror actuator (via power mirror switch),
Power window master switch,
Radiator fan relay,
Rear window defogger relay		 *1: With automatic dimming inside mirror
*2: With seat heater
*3: Without touch screen
B23 --- Not used  
B24 7.5 A EPS control unit,
Steering angle sensor,
VSA modulator-control unit		  
B25 7.5 A Not used  
B26 --- Not used  
B27 20 A Console accessory power socket (via console accessory power socket relay)  
B28 --- Not used  
B29* 7.5 A Front passenger's airbag cutoff indicator,
Front passenger's weight sensor unit		 *: USA and Canada models
B30 10 A Driver's door lock actuator  
B31 10 A Electric steering lock*1,
Engine start/stop switch,
Engine start/stop switch indicator*2,
Engine start/stop switch light,
Keyless access/TPMS control unit,
Keyless access/TPMS control unit (via engine start/stop switch)		 *1: Mexico models
*2: '17-18
B32 15 A Front passenger's door lock actuator, Right rear door lock actuator  
B33 15 A Left rear door lock actuator  
B34 7.5 A Left front parking light/daytime running light*1,
Left front side marker light*1,
Left inner taillight,
Left license plate light*1,
Left headlight*2,
Left taillight,
License plate light*2,
Right front parking light/daytime running light*1,
Right front side marker light*1,
Right inner taillight,
Right license plate light*1,
Right headlight*2,
Right taillight		 *1: '17-18
*2: '19-21
B35 7.5 A ACC combination switch light*2,
Audio remote-HFL switch lights,
A/T gear position indicator light,
Center display unit*3,
Center switch panel/interface dial light*3,
Climate control unit,
CMBS OFF switch light*2,
Cruise control combination switch light*1,
Driver's seat heater switch light*4,
Front passenger's seat heater switch light*4,
Glove box light,
Hazard warning switch light,
Moonroof switch light,
Multi information switch light,
Paddle shifter lights,
RDM switch light*2,
Roof console module lights,
VSA OFF switch light		 *1: Without LKAS/ACC/CMBS
*2: With LKAS/ACC/CMBS
*3: With touch screen
*4: With seat heater
B36 --- Not used  
B37* 30 A Stereo amplifier *: With touch screen
B38 10 A MICU (+B L H/L HI)  
B39 10 A MICU (+B R H/L HI)  
B40 --- Not used  
B41 20 A D/L DR unlock relay circuit (built into the under-dash fuse/relay box),
D/L lock relay circuit (built into the under-dash fuse/relay box),
D/L unlock relay circuit (built into the under-dash fuse/relay box), Trunk ACT relay circuit (built into the under-dash fuse/relay box)		  
No. B8 and No. B9 fuses in the under-dash fuse/relay box (via D/L unlock relay circuit (built into the under-dash fuse/relay box)),
No. B15 fuse in the under-dash fuse/relay box (via D/L DR unlock relay circuit (built into the under-dash fuse/relay box)),
No. B30, No. B32, and No. B33 fuses in the under-dash fuse/relay box (via D/L lock relay circuit (built into the under-dash fuse/relay box)),
Trunk lid release actuator (via trunk ACT relay circuit (built into the under-dash fuse/relay box))
B42 20 A Power window master switch  
B43 20 A Right rear power window motor (via right rear power window switch)  
B44 20 A Front passenger's power window switch  
B45 20 A Left rear power window motor (via left rear power window switch)  
B46 --- Not used  
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