P05A0 Active grille shutter stuck or out of position: the motorised shutters in front of the radiator are not reaching their commanded angle

Active grille air shutter stuck

Monitor

Mazda and Subaru describe it as a software-related check engine light on the models they list, with the shutter still working; Mazda says it stores the code immediately instead of running its fail-safe.

Source: how we rate severity

P05A0 in short

P05A0 means the active grille shutter, the motorised vanes in front of the radiator, is stuck or not reaching its commanded position. Mazda says it can be a software issue where the code sets even though the shutter works. Subaru and Volkswagen also have software or part fixes.

Active grille shutters close to cut drag and open to cool the engine. The computer commands an angle and sets P05A0 when the shutter does not get there.

Mazda bulletin 01-009-21-3799 says on 2019-2021 Mazda3 and 2020-2021 CX-30 the code was set at once instead of running the fail-safe, in which the shutter cycles open and closed up to three times to clear a temporary obstruction. Mazda fixes it with software.

Subaru has an engine computer reprogramming for P05A0 with battery drain and hanging engine speed, and Volkswagen blames incorrect software in the shutter motor on the 2015-2016 Jetta. Owners report a $900 quote for a Jetta shutter and a dealer report of the code on a 2017 CR-V.

Most likely causes

  1. Control software sets the code before the fail-safe (Mazda3, CX-30)

    Supported by vehicle data
    Why it ranks here
    Mazda 01-009-21-3799 says the code is stored while the shutter works because the software does not run the fail-safe first, and a software change fixes it.
    What would change this
    Rises on a listed Mazda with the shutter working normally. Falls if the shutter is stuck.
    How to test the engine control module (ecm / pcm)

  2. Engine computer or shutter motor software (Subaru, Volkswagen)

    Supported by vehicle data
    Why it ranks here
    Subaru 11-174-17R reprograms the computer for P05A0; Volkswagen 2043736 says the code is stored because of incorrect software in the shutter motor and lists an updated grille part.
    What would change this
    Rises on a listed vehicle with no physical damage. Falls if the shutter is jammed.

  3. Shutter jammed by debris, ice or damage

    Possible — needs testing
    Why it ranks here
    Mazda's fail-safe exists to clear a temporary obstruction, which shows the shutter can be blocked; an owner reports a Jetta shutter stuck.
    What would change this
    Rises if the shutter is visibly blocked or will not move by hand. Falls if it moves freely.

  4. Failed shutter actuator motor

    Possible — needs testing
    Why it ranks here
    A Jetta owner was quoted about $900 for the shutter; it is one report and the bulletin points to software first.
    What would change this
    Rises if the shutter does not move when commanded and software is current. Falls if it moves.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Read all codes and look at the grille shutters for debris, ice or damage; note if the shutter moves.

    Low riskTool: OBD-II scan tool, flashlight

  2. Ask a dealer whether a software update applies to your VIN and command the shutter with a scan tool.

    Best left to a shopTool: dealer scan tool

    Warning:This needs specialist tools and vehicle service information. Leave it to a shop.

Symptoms

  • Check engine light on
  • Battery drain after short trips (Subaru bulletin)
  • High or hanging engine speed after pressing the clutch (Forester bulletin)

How to fix

  1. Look at the shutters behind the front grille for debris or ice.

On your vehicle

Mazda

  • 2019–2021 · Mazda3

    Supported by vehicle data

    Mazda 01-009-21-3799 says P05A0 can set while the shutter works and is fixed by a software change. Whether the bulletin is still current is not verified.

  • 01-009-21-3799Status unverified

    P05A0 active air shutter opening angle abnormality

    2019–2021mazda3, cx-30 · NHTSA 10190953

    Control software sets the code at once instead of running the fail-safe; fixed with a software change.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Subaru

  • 2015–2017 · WRX

    Supported by vehicle data

    Subaru 11-174-17R reprograms the engine computer for P05A0. Whether the bulletin is still current is not verified.

  • 11-174-17RStatus unverified

    Engine computer reprogramming for P05A0

    2015–2018outback, legacy, wrx, forester · NHTSA 10131689

    Addresses a check engine light with P05A0, battery discharge after short trips and hanging engine speed (Forester only).

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Volkswagen

  • 2015–2016 · Jetta

    Supported by vehicle data

    Volkswagen 2043736 ties P05A0 to software in the active grille motor; an owner reports a $900 quote. Whether the bulletin is still current is not verified.

  • 2043736Status unverified

    MIL on with P05A3 and/or P05A0

    2015–2016jetta · NHTSA 10135063

    The code is stored because of incorrect software in the active grille motor; an updated grille part is listed.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Honda

No curated relationships for P05A0 yet.

All Engine cooling (thermostat) codes

P05A0 questions

Is the shutter really broken with P05A0?

Not always. Mazda says the code can set while the shutter works, and a software update clears it.

Sources and review

  1. Mazda 01-009-21-3799 (NHTSA 10190953): Mazda3 and CX-30 P05A0 active air shutter — Mazda Motor Corporation
  2. Subaru bulletin 11-174-17R (NHTSA 10131689): ECM reprogramming for P05A0, battery drain and hanging RPM — Subaru of America
  3. Volkswagen 2043736 (NHTSA 10135063): 2015-2016 Jetta MIL with P05A3 and/or P05A0 — Volkswagen of America
  4. NHTSA complaint ODI 11395041: Volkswagen Jetta 2015, P05A0 active grille air shutter stuck — NHTSA Office of Defects Investigation
  5. NHTSA complaint ODI 11748525: Honda CR-V 2017, dealer report P05A0 Active Grille Shutter malfunction — NHTSA Office of Defects Investigation
Last reviewed
Written by
Saurabh K.
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