2021 Toyota Tacoma — Fuse Box Diagram & Amperage

Quick answer

• Under-hood (engine compartment) fuse/relay box: Main power distribution for engine management (ECM/EFI), fuel pump, ignition, A/C clutch, ABS, headlamps, trailer power, blower motor feed, and key relays.
• Instrument panel (driver’s side kick-panel) fuse box: Body and cabin circuits such as radio/infotainment, 12V outlets/cigar lighter, gauges, SRS/airbag, HVAC controls, wipers/washer, turn/stop/tail, and OBD.
• Trunk/cargo: The Tacoma does not have a separate trunk fuse box. Trailer/towing power protection is integrated in the under-hood fuse/relay box; some models with bed/inverter options add breakers near the inverter assembly.

Note: Toyota uses circuit labels and positions that can vary slightly by trim and options. Always confirm the exact fuse number/position against the printed legend on the fuse box lid and the owner’s manual.

Under-hood fuse/relay box (engine compartment)

Location: Driver side of the engine bay near the battery under a snap-on cover. Inside the cover you’ll find a printed legend showing fuse/relay positions.

Typical fuses in this box (verify exact numbering/position on your lid):

Common relays in this box (labeling varies; see lid):

• Starter relay
• A/C compressor (MG CLT) relay
• EFI main relay
• Circuit opening (fuel pump) relay
• Headlamp relay(s)
• Horn relay
• Cooling fan relay(s) (as equipped)
• Trailer tow relay(s) (as equipped)

Instrument panel/driver kick-panel fuse box

Location: Behind the lower dash panel at the driver’s left kick area. Remove the small cover to access mini blade fuses. The legend for positions is molded on the back of the cover.

Typical fuses in this box (verify exact numbering/position on your lid):

Relays/Junctions in this area (varies by trim):

• Blower motor relay (some trims under dash, others in engine bay)
• Accessory relay
• Defogger relay (if not under-hood)

Cargo/bed/trailer power protection (if equipped)

The Tacoma does not have a trunk fuse box. Trailer power and bed options are protected in the engine compartment box. Notes:

• Trailer power/stop/tail/charge fuses and tow relays are in the under‑hood box (tow package).
• If equipped with a 120V AC bed outlet/inverter, dedicated breakers/fuses are near the inverter assembly; they are not in the main fuse boxes. Consult the inverter label and owner’s manual for exact protection.

How to test a fuse

• Visual: Remove the suspect fuse and look through the transparent body. A melted/broken element indicates a blown fuse. This is quick but can miss hairline breaks.
• Continuity test (best): With a digital multimeter set to continuity/ohms, probe both blades. A good fuse reads near 0 ohms or beeps. Infinite resistance means it’s blown.
• Voltage drop: With the circuit powered, probe the two test tabs on top of the fuse. Both tabs should show battery voltage relative to ground. Voltage on only one tab indicates an open fuse.

Always replace with the same amperage and style. If the new fuse blows immediately, stop and diagnose the underlying shorted component or wiring.

Common blown fuses on this vehicle

• 12V outlet/cigar lighter (CIG/P/OUTLET 15A blue): Often blown by phone chargers or accessories. Check for coins/debris in the socket and try a known‑good charger before replacing.
• Radio/infotainment (RADIO/AV 15A blue): Can blow after accessory wiring or aftermarket installs. Inspect any added harnesses and ensure no pins are shorted behind the head unit.
• Tail/park (TAIL 10A red): Trailer wiring faults are the most common cause. Disconnect the trailer, replace the fuse, and retest. Inspect the 7‑pin connector for corrosion.
• Stop lamp (STOP 10A red): Trailer connector corrosion or a pinched CHMSL wire at the tailgate can short this circuit.
• Headlamp fuses (H-LP LO/HI 10–15A): After bulb replacement, ensure the correct wattage bulb and that the connector isn’t melted.
• Fuel pump (FUEL PUMP 15A blue): Rare to blow without a short. If it does, inspect the pump harness at the tank and the frame ground near the bed.
• ABS (ABS NO.1/NO.2 30–40A J-case): If either blows, do not drive. Check for rubbed‑through wheel speed sensor leads at the knuckles and inspect the pump/module area for damage.
• Blower (HTR 40A J-case): If the blower is seized or the blower resistor/driver shorts, the main HTR fuse can blow. Spin the blower by hand and test current draw.
• Trailer fuses (TOW TAIL 10A, TOW STOP 20A, TRAILER BAT/CHARGE 30A): Almost always a trailer harness short. Unplug the trailer and inspect/repair wiring before replacing.

Important: Toyota numbering/positions differ by trim. Always match your fuse to the printed legend inside the fuse box lid. When in doubt, use the circuit label (EFI, FUEL PUMP, H-LP, etc.) and the amp/color to locate the correct fuse.

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