Subaru Legacy recurring battery issues due to alternator failure despite recent replacement on Subaru Legacy

Submitted by tnmorgen · Jun 23, 2025
Published by RepairPal

Problem overview

Some Subaru Legacy owners report experiencing recurring battery issues even after recent replacements, often linked to alternator failure. These owners note that a faulty alternator can trigger the red battery light, signaling a malfunction in the charging system. Symptoms of a failing alternator include the battery not charging properly while the vehicle is running, dimming lights due to insufficient power, and unusual noises like whining or grinding sounds. Additionally, some owners find that corroded battery terminals contribute to battery problems by creating resistance that hinders charging. In some cases, the battery warning light may not activate until the vehicle stalls due to a lack of power, which can indicate a bad ground connection issue. Addressing these alternator-related concerns promptly is essential to prevent further battery challenges and ensure the vehicle's proper functioning.

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Subaru Legacy vehicles with this problem

1 model year affected
Average mileage: 137,000 miles
(137,000 - 137,000)

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