2018 Tesla Model S – Fuse Box Diagram & Amperage

Quick Answer

The 2018 Tesla Model S features multiple fuse box locations to protect its complex electrical systems. You'll find fuse boxes located in the front trunk (frunk), the left-hand side of the dashboard (driver's side kick panel), and the rear cargo area (trunk).

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Front Trunk (Frunk) Fuse Box

The front trunk fuse box in your 2018 Tesla Model S houses fuses for many critical power distribution and high-current systems. Always verify the fuse legend on the inside of your fuse box cover, as configurations can vary slightly due to trim levels and options.

Fuse #	Amp	Color	Circuit / Component Protected
F1	25	Clear	Front Drive Unit Inverter Pre-Charge
F2	10	Red	AC Compressor Control
F3	15	Blue	A/C Blower Motor
F4	10	Red	Headlight - Left Low Beam
F5	10	Red	Headlight - Right Low Beam
F6	7.5	Brown	Headlight - Left High Beam
F7	7.5	Brown	Headlight - Right High Beam
F8	20	Yellow	Front Auxiliary Power Outlet (12V)
F9	15	Blue	Wiper Motor
F10	30	Green	Front Bumper Area (Active Air Flaps/Sensors)
F11	5	Tan	ABS/Stability Control Module (Power Supply)
F12	20	Yellow	Air Suspension Compressor (if equipped)
F13	10	Red	Horn
F14	5	Tan	Main Body Controller (MBC) Front Power
F15	15	Blue	Fog Lights (if equipped)
F16	10	Red	Radiator Fan (Low Speed)
F17	15	Blue	Radiator Fan (High Speed)
F18	5	Tan	Powertrain Control Module (PCM)/ECM
F19	15	Blue	DC-DC Converter Control
F20	25	Clear	Brake System Vacuum Pump

Relay Locations (Front Trunk):

The front trunk fuse box also contains several relays. These are typically larger cubic components than fuses. Common relays found here include:

• R1: Cooling Fan Relay - Controls the radiator cooling fan operations.
• R2: A/C Compressor Clutch Relay - Engages and disengages the A/C compressor clutch.
• R3: Horn Relay - Activates the vehicle's horn.
• R4: Headlight Relays (Left/Right) - Controls power to the high beam headlights.

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Dashboard Fuse Box (Driver's Side Kick Panel)

Located on the left-hand side of the dashboard, accessible by removing the side kick panel, this fuse box primarily protects interior electrical components and control modules. Always refer to the diagram on the fuse box cover for the exact layout.

Fuse #	Amp	Color	Circuit / Component Protected
F1	5	Tan	Infotainment System / Media Control Unit (MCU)
F2	10	Red	Instrument Cluster / Display
F3	5	Tan	Steering Wheel Controls
F4	7.5	Brown	Power Window - Driver Side
F5	7.5	Brown	Power Window - Passenger Side Front
F6	7.5	Brown	Power Window - Rear Left
F7	7.5	Brown	Power Window - Rear Right
F8	5	Tan	Door Lock Control Module
F9	10	Red	Mirror Adjustments / Heated Mirrors
F10	15	Blue	Seat Heaters - Driver Side
F11	15	Blue	Seat Heaters - Passenger Side Front
F12	10	Red	Sunroof / Panoramic Roof Controls
F13	5	Tan	Airbag Control Module (SRS)
F14	10	Red	Occupant Classification System
F15	5	Tan	Diagnostic Port (OBD-II)
F16	7.5	Brown	Key Fob Receiver / immobilizer
F17	15	Blue	Interior Lighting / Dome Lights
F18	5	Tan	Lane Keep Assist / Auto Pilot Sensors
F19	10	Red	Wiper / Washer Stalk
F20	7.5	Brown	Hazard Warning Lights

Relay Locations (Dashboard):

Relays in the dashboard fuse area are less common than in the frunk but can include:

• R1: Accessory Relay - Controls power to various interior accessories, often tied to vehicle power status.

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Rear Cargo Area (Trunk) Fuse Box

The rear fuse box, situated in the trunk or cargo area, typically behind a trim panel, protects components located towards the rear of the vehicle, including those related to charging, rear lighting, and certain vehicle systems. Check your vehicle's fuse box cover for accurate information.

Fuse #	Amp	Color	Circuit / Component Protected
F1	20	Yellow	Rear Auxiliary Power Outlet (12V) / USB Ports
F2	10	Red	Tail Lights - Left
F3	10	Red	Tail Lights - Right
F4	7.5	Brown	Brake Lights
F5	5	Tan	Reverse Lights
F6	10	Red	License Plate Lights
F7	15	Blue	Power Liftgate / Trunk Release
F8	25	Clear	Rear Drive Unit Inverter
F9	30	Green	Charging Port / Onboard Charger Control
F10	15	Blue	Rear HVAC Blower Motor (if equipped)
F11	10	Red	Trailer Brake Control Module (if equipped with Tow Package)
F12	5	Tan	Rear Camera / Parking Assist Sensors
F13	7.5	Brown	Rear Defroster Relay Control
F14	10	Red	Fuel Pump Control Module (Though electric, for low voltage control if applicable, or for related system)
F15	15	Blue	Seat Heaters - Rear Left
F16	15	Blue	Seat Heaters - Rear Right
F17	5	Tan	TPM System (Tire Pressure Monitoring)
F18	5	Tan	Active Spoiler Motor (if equipped)
F19	20	Yellow	Autopilot Hardware Power Supply
F20	10	Red	Body Control Module (BCM) Rear Power

Relay Locations (Rear Cargo Area):

The rear fuse panel may include relays for:

• R1: Power Liftgate Relay - Controls the operation of the motorized trunk/liftgate.
• R2: Rear Defroster Relay - Activates the rear window defroster.
• R3: Trailer Tow Relays - If equipped with a tow package, specific relays for trailer lights and brake control may be present.

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How to Test a Fuse

Testing a fuse is a straightforward process that can help diagnose electrical issues. You'll need a multimeter or a fuse tester for this. Here's how:

1. Locate the Fuse Box: Identify the correct fuse box for the circuit you're troubleshooting.
2. Turn Off the Vehicle: Ensure the ignition is off and keys are removed (if applicable) to prevent accidental shorts or injury.
3. Identify the Suspect Fuse: Consult your vehicle's fuse diagram (usually on the fuse box lid or in your owner's manual) to find the fuse for the circuit in question.
4. Remove the Fuse: Use a fuse puller (often located in the fuse box) or small pliers to carefully remove the fuse.
5. Visually Inspect: Hold the fuse up to the light. If the metal wire or filament inside is broken or melted, the fuse is blown and needs replacement.
6. Test with a Multimeter (for less obvious breaks):
   • Set your multimeter to the "ohms" or continuity setting (usually indicated by a speaker icon).
   • Touch the probes to the two metal blades of the fuse. If the multimeter beeps or shows a reading close to zero ohms, the fuse is good. If there's no beep or an "OL" (open loop) reading, the fuse is blown.
7. Replace the Fuse: If the fuse is blown, replace it with a new fuse of the exact same amperage rating and type. Using a fuse with a higher rating can cause serious electrical damage or fire.

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Common Blown Fuses on This Vehicle

While any fuse can blow, some are more prone to failure due to the nature of their circuits. On a 2018 Tesla Model S, some commonly blown fuses or circuits to check first include:

• Accessory Power Outlets (Cigar Lighter / 12V Outlets): These fuses (F8 in the frunk, F1 in the rear cargo) often blow due to overloaded accessories, faulty chargers, or foreign objects shorting the outlet. If your phone charger or other accessories aren't working, check these first.
• Wiper Motor Fuse (F9 in Frunk): If your wipers stop working, especially after operating in heavy snow or ice, this fuse can sometimes be the culprit. A seized wiper arm or motor can also cause it to blow.
• Headlight Fuses (F4, F5, F6, F7 in Frunk): While less common with modern LED systems, issues with headlight control modules or wiring can sometimes lead to blown fuses for individual headlight circuits.
• Infotainment System / MCU Fuse (F1 in Dash): If your central touchscreen or media features are unresponsive, a blown fuse for the infotainment system or Media Control Unit (MCU) could be the cause. This is a common troubleshooting step for screen-related issues.
• Air Suspension Compressor Fuse (F12 in Frunk): If your air suspension isn't adjusting or a warning light is on, check this fuse. A failing compressor can draw excessive current and blow the fuse.
• Trailer Brake Control Module Fuse (F11 in Rear Cargo): If you're experiencing issues with your trailer brakes, especially after connecting a new trailer, check this fuse first. Miswiring on a trailer is a very common cause of this fuse blowing.

What to check first: Before automatically replacing a fuse, consider what happened leading up to the electrical failure. Did you plug in a new device? Did it rain heavily? Did you hit a pothole? This context can help pinpoint the root cause. If a fuse blows repeatedly, there's an underlying electrical issue that needs professional diagnosis, rather than just replacing fuses.

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