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If your Subaru’s AWD warning light is flashing, pull over somewhere safe and check all four tires for a puncture, low pressure or a size mismatch. Subaru warns that driving with the flashing light can damage the powertrain. A steady light does not have one universal meaning across Subaru models, so check the owner’s manual for your exact year and configuration.
What to do when the AWD warning light flashes
- Park safely. Subaru’s owner manual says to promptly stop in a safe location when the AWD warning light flashes.
- Inspect all four tires. Look for a puncture, visible loss of air or a tire that differs in size from the others. Check pressures against the specifications for your vehicle; a pressure gauge can help with that check but cannot diagnose an AWD fault.
- Do not continue driving with the warning flashing. Subaru warns that continued driving can lead to powertrain damage. If you cannot identify and safely address the tire issue, arrange assistance rather than driving on.
These instructions come from Subaru’s owner manual; light behavior and instructions can vary by model, year and transmission, so consult the manual for your specific vehicle.
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What a flashing light may indicate
Subaru manuals associate a flashing AWD warning with tires that differ in diameter or excessively low air pressure in one or more tires. Start by checking the full set, not just the tire that looks low: an unsuitable or mismatched tire can also matter. The warning is not, by itself, a diagnosis of which tire or component is at fault.
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How a temporary spare affects the warning
A temporary spare may cause the AWD warning to flash. Subaru says to limit use of the temporary spare to the minimum time necessary and replace it with a conventional tire as soon as possible. Follow the spare-tire and driving instructions in your vehicle’s manual.
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What if the AWD light stays on steadily?
A steady AWD light should not be treated as equivalent to a flashing warning. The reviewed Subaru manuals do not establish one universal explanation or reset procedure for every model and configuration. Check the exact manual for your year, model and transmission; if it directs you to seek service or the warning persists, contact an authorized Subaru retailer.
Choosing a replacement tire
Subaru recommends replacing tires with the same tires originally equipped. If you choose another brand, Subaru strongly recommends matching the original size and style; exact fitment depends on the vehicle. Refer to the owner’s manual or ask an authorized retailer before replacing a tire, particularly when only one tire needs replacement. See Subaru’s tire replacement recommendations.
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What a pressure gauge can—and cannot—tell you
A gauge can help you compare tire pressures with your vehicle’s specified values while checking for air loss. It cannot determine whether the AWD system has a fault, nor does checking pressure alone rule out a tire-size or diameter mismatch. If the warning remains after the tire issue is addressed, use the vehicle-specific manual and arrange service as directed.
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