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Home >> Honda >> 2021 >> Ridgeline RTL-E >> Repair and Diagnosis (Single Page) >> Electrical >> Component Locations >> Electrical System - Testing & Troubleshooting >> Fuse To Components Index >> Fuse to Components Index (2019) >> Under-Hood Fuse/Relay Box
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Under-Hood Fuse/Relay Box

Fig 1: Under-Hood Fuse/Relay Box Components Location
GHH451876Courtesy of HONDA, U.S.A., INC.
Under-Hood Fuse/Relay Box Legend

Fuse Number Amps Component(s) or Circuit(s) Protected
A1-1 70 A AC inverter unit (via AC inverter relay) (with AC power outlet)
A1-2 30 A Rear blower motor (via rear blower motor relay) (without AC power outlet)
A1-3 40 A VSA modulator-control unit
A1-4 20 A VSA modulator-control unit
A1-5 30 A Radiator fan motor (via radiator fan relay) (without AC power outlet)
A1-6 150 A Alternator, No. A2-1, No. A2-2, No. A2-3, No. A2-6, No. A2-7 (with stereo amplifier), No. A2-8 (without AC power outlet), No. A2-10 (with AC power outlet), No. A3-1 (with AC power outlet), No. A3-4 (with AC power outlet), No. A21, No. A22, No. A23, No. A24, No. A25, No. A26 (with AC power outlet and front fog light or without AC power outlet), No. A27 (with heated steering wheel), No. A28, and No. A29 fuses in the under-hood fuse/relay box
A2-1 30 A A/C condenser fan motor (via A/C condenser fan relay)
A2-2 30 A Windshield wiper motor (via windshield wiper motor intermittent relay circuit and windshield wiper motor high/low relay circuit (built into the relay circuit board))
A2-3 20 A Windshield washer motor relay, Windshield washer motor (via windshield washer motor relay)
A2-4 20 A Not used
A2-5 20 A Not used
A2-6 40 A Front blower motor (via front blower motor relay)
A2-7 30 A Stereo amplifier (with stereo amplifier)
A2-8 30 A Rear window defogger (via rear window defogger relay) (without AC power outlet)
A2-9 40 A Not used
A2-10 30 A Rear window defogger (via rear window defogger relay) (with AC power outlet)
A2-11 20 A Not used
A3-1 30 A Rear blower motor (via rear blower motor relay) (with AC power outlet)
A3-2 30 A Not used
A3-3 30 A Not used
A3-4 30 A Radiator fan motor (via radiator fan relay) (with AC power outlet)
A4 10 A [With AC power outlet]: Brake lights (via brake light relay), Brake lights (via brake pedal position switch and brake light relay), High mount brake light (via brake light relay), High mount brake light (via brake pedal position switch and brake light relay), Keyless access/TPMS control unit (via brake pedal position switch), MICU (via brake pedal position switch), PCM (via brake pedal position switch), Trailer electric brake connector (via brake pedal position switch), Trailer lighting control unit (via brake light relay), Trailer lighting control unit (via brake pedal position switch and brake light relay), VSA modulator-control unit (via brake light relay), VSA modulator-control unit (via brake pedal position switch and brake light relay)
[Without AC power outlet]: No. C25 and No. C27 fuses in the under-dash fuse/relay box (via small light relay circuit (built into the relay circuit board)), Small light relay circuit (built into the relay circuit board)
A5 --- Not used
A6 10 A [With AC power outlet]: No. C25 and No. C27 fuses in the under-dash fuse/relay box (via small light relay circuit (built into the relay circuit board)), Small light relay circuit (built into the relay circuit board)
[Without AC power outlet]: Brake lights (via brake light relay), Brake lights (via brake pedal position switch and brake light relay), High mount brake light (via brake light relay), High mount brake light (via brake pedal position switch and brake light relay), Keyless access/TPMS control unit (via brake pedal position switch), MICU (via brake pedal position switch), PCM (via brake pedal position switch), Trailer electric brake connector (via brake pedal position switch), Trailer lighting control unit (via brake light relay), Trailer lighting control unit (via brake pedal position switch and brake light relay), VSA modulator-control unit (via brake light relay), VSA modulator-control unit (via brake pedal position switch and brake light relay)
A7 --- Not used
A8 7.5 A [With AC power outlet]: Radiator fan relay (via diode)
10 A [Without AC power outlet]: Left headlight (low beam)
A9 --- Not used
A10 10 A [With AC power outlet]: Left headlight (low beam)
[Without AC power outlet]: Right headlight (low beam)
A11 10 A [With AC power outlet]: Right headlight (low beam)
7.5 A [Without AC power outlet]: Radiator fan relay (via diode)
A12 15 A [With AC power outlet]: Ignition coil relay circuit (built into the relay circuit board), Ignition coils (via Ignition coil relay circuit (built into the relay circuit board))
20 A [Without AC power outlet]: Injector control module (two wires)
A13 15 A [With AC power outlet]: PCM (via electronic throttle control system (ETCS) control relay circuit (built into the relay circuit board))
20 A [Without AC power outlet]: Headlight relay, No. A8 and No. A10 fuses in the under-hood fuse/relay box (via headlight relay)
A14 15 A AC inverter unit (via AC inverter ACC relay and AC power outlet switch) (with AC power outlet), AC inverter relay (via AC inverter ACC relay) (with AC power outlet), AC power outlet switch (with AC power outlet), USB charger unit A (with USB charger unit A)
A15 10 A [With AC power outlet]: Automatic lighting control unit-sensor (without automatic wiper), Automatic lighting/rain sensor (with automatic wiper), CAN gateway (with CAN gateway), Data link connector, Gauge control module, HomeLink ® unit (with HomeLink ®), Keyless access/TPMS control unit, MICU, Multipurpose camera unit (with multipurpose camera unit), Power mirror control unit (with DPMS), Power seat control unit (with DPMS), Power window master switch
15 A [Without AC power outlet]: Front fog light relay (with front fog light), Front fog lights (via front fog light relay) (with front fog light)
A16 15 A [With AC power outlet]: CKP sensor (via PGM-FI main relay 1 circuit (built into the relay circuit board)), CMP sensor (via PGM-FI main relay 1 circuit (built into the relay circuit board)), Electronic throttle control system (ETCS) control relay circuit (built into the relay circuit board) (via PGM-FI main relay 1 circuit (built into the relay circuit board)), Injector relay (via PGM-FI main relay 1 circuit (built into the relay circuit board)), No. A11 fuse in the under-hood fuse/relay box (via PGM-FI main relay 1 circuit (built into the relay circuit board)), PCM (via PGM-FI main relay 1 circuit (built into the relay circuit board)), PGM-FI main relay 1 circuit (built into the relay circuit board)PGM-FI main relay 2 (via PGM-FI main relay 1 circuit (built into the relay circuit board))
[Without AC power outlet]: MICU
A17 20 A Recline motor (via front passenger's power seat adjustment switch) (with power seat and without DPMS)
A18 20 A Slide motor (via front passenger's power seat adjustment switch) (with power seat and without DPMS)
A19 20 A Engine mount control unit (via active control engine mount (ACM) control relay)
A20 7.5 A A/C compressor clutch (via A/C compressor clutch relay)
A21 15 A [With AC power outlet]: MICU
[Without AC power outlet]: CKP sensor (via PGM-FI main relay 1 circuit (built into the relay circuit board)), CMP sensor (via PGM-FI main relay 1 circuit (built into the relay circuit board)), Electronic throttle control system (ETCS) control relay circuit (built into the relay circuit board) (via PGM-FI main relay 1 circuit (built into the relay circuit board)), Injector relay (via PGM-FI main relay 1 circuit (built into the relay circuit board)), No. A11 fuse in the under-hood fuse/relay box (via PGM-FI main relay 1 circuit (built into the relay circuit board)), PCM (via PGM-FI main relay 1 circuit (built into the relay circuit board)), PGM-FI main relay 1 circuit (built into the relay circuit board)PGM-FI main relay 2 (via PGM-FI main relay 1 circuit (built into the relay circuit board))
A22 15 A EVAP canister vent shut valve (via PGM-FI subrelay circuit (built into the relay circuit board)), Front A/F sensor (bank 2, sensor 1) (via PGM-FI subrelay circuit (built into the relay circuit board)), Front secondary HO2S (bank 2, sensor 2) (via PGM-FI subrelay circuit (built into the relay circuit board)), PGM-FI subrelay circuit (built into the relay circuit board), Rear A/F sensor (bank 1, sensor 1) (via PGM-FI subrelay circuit (built into the relay circuit board)), Rear secondary HO2S (bank 1, sensor 2) (via PGM-FI subrelay circuit (built into the relay circuit board))
A23 20 A [With AC power outlet]: Injector control module (two wires)
15 A [Without AC power outlet]: Ignition coil relay circuit (built into the relay circuit board), Ignition coils (via Ignition coil relay circuit (built into the relay circuit board))
A24 20 A [With AC power outlet]: Headlight relay, No. A8 and No. A10 fuses in the under-hood fuse/relay box (via headlight relay)
15 A [Without AC power outlet]: PCM (via electronic throttle control system (ETCS) control relay circuit (built into the relay circuit board))
A25 20 A No. A4 and No. A6 fuses in the under-hood fuse/relay box
A26 15 A [With AC power outlet]: Front fog light relay (with front fog light), Front fog lights (via front fog light relay) (with front fog light)
10 A [Without AC power outlet]: Automatic lighting control unit-sensor (without automatic wiper), Automatic lighting/rain sensor (with automatic wiper), CAN gateway (with CAN gateway), Data link connector, Gauge control module, HomeLink ® unit (with HomeLink ®), Keyless access/TPMS control unit, MICU, Multipurpose camera unit (with multipurpose camera unit), Power window master switch
A27 10 A Heated steering wheel control unit (via heated steering wheel relay and cable reel) (with heated steering wheel)
A28 10 A Horn relay, Horns (via horn relay)
A29 20 A ANC/active sound control unit, Audio unit (without navigation), Audio-navigation unit (with navigation), USB charger unit B (with USB charger unit B)