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Subaru Ascent 2018-2026 Owner's Manual: Tire pressure monitoring system (TPMS) (U.S.-spec. models)

Subaru Ascent TPMS warning light indicator and tire pressure monitoring system display

The tire pressure monitoring system (TPMS) in the Subaru Ascent is designed to continuously monitor tire pressure and alert the driver when one or more tires are significantly underinflated. This system enhances safety by helping to reduce the risk of tire-related incidents and ensuring optimal driving performance.

The Subaru Ascent TPMS becomes active only when the vehicle is driven at speeds exceeding approximately 20 mph (32 km/h). It is important to understand that the system may not instantly detect a sudden loss of pressure, such as a rapid deflation caused by a puncture or sharp object.

WARNING

  • If the low tire pressure warning light illuminates while driving the Subaru Ascent, do not apply the brakes abruptly. Instead, follow these steps carefully to maintain control of the vehicle.

    Sudden braking may result in loss of control, leading to serious injury or vehicle damage.

    1. Maintain a straight driving path while gradually reducing speed.
    2. Carefully steer the Subaru Ascent to a safe location off the road.
    3. Inspect all four tires and adjust their pressure to the recommended COLD tire pressure indicated on the label located on the driver’s side door pillar.

    Keep in mind that even short driving distances can increase tire temperature and pressure. Always allow the tires to cool before making accurate pressure adjustments.

    The TPMS in the Subaru Ascent does not operate while the vehicle is stationary. After adjusting tire pressure, drive at speeds above 20 mph (32 km/h) to allow the system to re-evaluate tire conditions. If pressures are within acceptable limits, the warning light should turn off after a short period.

    If the warning light remains illuminated while driving, it may indicate significant tire damage or a rapid air leak that requires immediate attention.

    In the event of a flat tire, replace it with a spare tire as soon as possible to maintain safe operation of the Subaru Ascent.

    Always prioritize safety and avoid prolonged driving with underinflated or damaged tires.

  • If a spare tire is installed or a wheel is replaced without transferring the original TPMS sensor, the warning light will flash for approximately one minute and then remain illuminated.

    This indicates that the Subaru Ascent TPMS cannot monitor all wheels. Contact a SUBARU dealer promptly for sensor installation or system reset.

  • If a tire is repaired using liquid sealant, the TPMS sensor and valve may not function correctly afterward.

    In such cases, have the Subaru Ascent inspected by a qualified service provider. The sensor and valve should be replaced when installing a new tire.

    The wheel itself may be reused if it remains undamaged and any sealant residue has been thoroughly removed.

    Avoid using aerosol or liquid sealants whenever possible, as they can interfere with TPMS operation and lead to system malfunctions.

    If the warning light continues to illuminate after blinking for about one minute, arrange for immediate inspection by a SUBARU dealer.

The Subaru Ascent TPMS is a valuable safety feature that helps maintain proper tire condition and vehicle stability, but it should always be complemented by regular manual tire inspections and responsible driving habits.

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