Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with how well the second battery is holding its charge. It's like having a flashlight that doesn't stay bright for long because the batteries are weak.
The vehicle's control module has identified an issue with the performance of the secondary battery's state of charge.
P00FD indicates that the Engine Control Module (ECM) or Battery Management System (BMS) has detected that the secondary battery (Battery B) is not maintaining its state of charge as expected. This could be due to battery degradation, charging system issues, or electrical drain.
• Battery warning light on dashboard
• Difficulty starting the vehicle
• Dimming headlights or electrical accessories
• Degraded or faulty secondary battery
• Faulty alternator or charging system
• Excessive electrical drain or parasitic draw
ECM: Engine Control Module
BMS: Battery Management System
• Check the battery voltage and state of charge.
• Inspect the alternator and charging system for proper operation.
• Check for any parasitic electrical drain when the vehicle is off.
• Replace the secondary battery if it is faulty.
• Repair or replace the alternator if it is not charging properly.
• Identify and fix any sources of parasitic drain.
• Multimeter
• Battery tester
• Diagnostic scan tool
$100 - $400
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly check battery health.
• Ensure the charging system is functioning properly.
• Minimize electrical accessory use when the engine is off.
Battery Performance Issue
• Avoid using electrical accessories when the car is off.
• Get the battery and charging system checked regularly.
Battery issues may be covered under the vehicle's powertrain or battery warranty. Check with the manufacturer.
This code has become more common with the increased use of hybrid and electric vehicles that rely on multiple battery systems.
Moderate – Addressing this issue promptly can prevent being stranded due to a dead battery.
Driving with a faulty battery system can lead to vehicle shutdowns and safety hazards. Ensure repairs are made to avoid potential risks.
• Vehicle parked with engine off
• Vehicle running with electrical accessories on
The secondary battery is typically located in the trunk or rear of the vehicle, depending on the make and model.
Q: Can I drive with a P00FD code?
A: It's possible, but not recommended. A faulty battery can lead to unexpected vehicle shutdowns.
Q: How do I know if my battery is the problem?
A: A battery test can determine if the battery is holding its charge properly.
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