Avoid Inactivity
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Wonder why your hybrid car is showing a check engine light shortly after returning from a holiday? Yes, it happens a lot. Here’s why.
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NiMH batteries naturally self-discharge, meaning they lose capacity just being sitting around doing nothing. Each module in your NiMH battery pack discharges at a slightly different rate even when new. As the battery ages, this variation becomes increasingly pronounced. If left inactive for too long, the imbalance in remaining capacity between modules leads to significant block voltage differences, triggering diagnostic trouble codes (DTC) and illuminating the check engine light.
Key takeaways:
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The older the battery, the more frequently it needs to be run to prevent this issue.
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Avoid long periods of inactivity—run the car for at least 30 minutes once or twice a week for all car ages.