Is it safe to drive with Toyota Prius Gen2 12V Auxiliary Battery Failure?

Generally safe to drive for short distances, but the fault should be diagnosed and repaired promptly.

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Toyota Prius Gen2 12V Auxiliary Battery Failure — Toyota Prius 2004 | MyCarFault

Toyota Prius Gen2 12V Auxiliary Battery Failure

Toyota Prius 2004 1NZ-FXE 1.5 Hybrid

Safe to Drive?

✅ Safe to Drive

Urgency Level

🟠 Fix Soon

The 12V auxiliary battery in Gen2 Prius fails after 4-6 years, causing the car to appear completely dead, display multiple warning lights or fail to enter Ready mode. This is the most common Prius breakdown. The 12V is a standard AGM battery (size S34B20R) and costs £80-150 to replace. Preventive replacement every 5 years is recommended.

Repair / Solution

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Toyota Prius Gen2 12V Auxiliary Battery Failure

Repair / Solution

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