Wrx Fuse Box Diagram

Reading the WRX Fuse Box Layout

The 2015 and newer WRX uses three separate fuse panels. The primary one sits on the driver's side of the engine bay, the second is tucked behind a panel on the left side of the dashboard near the steering column, and the third is in the rear cargo area on the right trim piece. Each box has a molded diagram printed directly on its cover, which Subaru got right for once. Still, the plastic degrades over time and the printing fades after a few years in sunlight, which is why most people end up looking for a paper version online. The under-hood box handles all high-current circuits. Main relays, the ABS module, the headlights, the cooling fans, the audio amp, and the supplemental restraint system all route through here. The fuses are a mix of blade-type and mini blade-types, rated from 5A to 60A. The 60A main fuse is the one that breaks when something downstream goes truly wrong, not just a shorted accessory. If that one is blown, you are dealing with a wiring problem, not a bad bulb.

Wrx Fuse Box Diagram Where to Find It

The factory diagram lives in the owner's manual, which most people discard after the first year. You can also find it as a standalone sheet in the workshop manual subscription, or downloaded from Subaru's parts portal by entering your VIN. VIN-specific diagrams matter because the 2017 facelift changed the cargo-area box layout slightly, adding circuits for the EyeSight camera module that weren't present in the 2015 and 2016 models. If you grab a generic PDF without checking the model year, you will be looking at the wrong fuse for the heated mirrors or the front radar unit. I spent an afternoon chasing a parasitic drain on a 2016 WRX with the aftermarket stereo installed. The manual showed fuse #12 in the cargo box as "Audio," but the actual car had the amp powered through a different circuit because the dealer had repositioned the wiring during a recall service. I ended up pulling every fuse one at a time with a $3 puller tool from AutoZone and found the draw was on a fuse the diagram didn't even label. The workaround was tracing the blue wire from the head unit back to the factory harness tap point behind the glovebox, then splicing a switched power feed instead of tapping into an always-on circuit. That fixed the drain from about 80mA down to 12mA. The cargo-area fuse box is the one people mess up most. It houses the radio, the HVAC control module, the airbag ECU, and the backup camera relay. The labels on the cover are easy to misread because Subaru uses abbreviations like "TAIL," "DRL," and "STOP" without explaining which is which. TAIL is the parking light circuit, DRL is the daytime running lights, and STOP is the brake light switch. Confusing DRL and STOP cost me a customer two hours of diagnosis once because they replaced the brake light switches three times before realizing the actual fault was a corroded pin in the DRL relay socket.

How to Approach a Fuse Problem

Start by verifying the failure. A blown fuse tells you something drew too much current, but it does not tell you why. Test the component that the fuse protects before you replace the fuse and hope for the best. Use a multimeter set to resistance mode on the device side of the circuit. If you get a reading near zero ohms, you have a hard short and need to trace the wiring. If the resistance is in the expected range for that component, the fuse blew from a momentary surge, which happens more often than people think with cooling fans and solenoids. When replacing fuses, use OEM Subaru or ATC-style blade fuses from a reputable brand. The cheap no-name fuses from gas station racks often have inconsistent ratings. I have seen a 15A fuse blow at 12A and a 20A fuse carry 24A without opening. That inconsistency means your circuit is either under-protected or you keep blowing fuses that should not be blowing. The difference in price is about two dollars and it matters more than you would expect. Another thing the diagrams do not make clear is that some fuses serve dual purposes depending on trim level. The 2018 WRX Limited has an additional amplifier fuse in the under-hood box that the Base model does not. If you are swapping parts between trims or installing an aftermarket part, check the fuse rating for your specific trim, not the base model chart. Putting a higher amperage fuse in to accommodate an aftermarket amp is the fastest way to melt a factory harness. The wiring gauge in those circuits is typically 16 to 18 AWG, which cannot handle much more than the factory fuse rating before insulation starts softening.

The dashboard fuse box is smaller but more frustrating to access. You have to remove the lower kick panel on the driver side, and on some model years the panel clips break if you are not careful. Once it is open, the fuses are densely packed and the diagram on the cover is the only reference. There is no label on the individual fuse holders themselves. I recommend taking a photo of the open box before you start pulling anything so you have a visual reference if a fuse gets mixed up during reassembly. Putting a 10A fuse back into a 15A slot might work temporarily, but it will blow again the next time that circuit sees a load spike, and you will have lost the protection the original rating was designed to provide.

Common Failure Points the Diagram Won't Show You

The subwoofer amp ground point on the 2016 and newer models is located behind the right-side cargo trim, near the fuse box. It corrodes. Not from water intrusion, but from normal moisture cycling in the cabin. The ground strap loosens, resistance climbs, and the amp throws codes or cuts out randomly. Cleaning the contact with sandpaper and applying dielectric grease solves it, but only if you know where the ground is in the first place. The fuse diagram does not include grounding points, which is a gap every DIYer runs into. The under-hood relay for the electric cooling fan is another known issue. The relay socket corrodes internally, causing intermittent fan operation. The fuse stays good, the relay clicks, but the fan does not spin because the socket contacts are pitted. Replacement of the socket, not just the relay, is the proper fix. Swapping in a new relay into a corroded socket will work until the new relay contacts also degrade, which takes a few months at most. If you need a clean reference diagram, Subaru's own service literature through the Suburu TechInfo website is the most accurate source, though it requires a paid subscription. Free PDFs on forums are usually scans of the owner's manual pages, which are lower resolution and sometimes crop out the smaller fuse numbers along the edges. For anything beyond a basic fuse swap, the factory manual is worth the subscription cost if you plan to do electrical work on the car beyond replacing blown fuses.