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 is having trouble controlling the battery charger. It's like when your phone charger isn't working right, and your phone isn't charging properly.
The P0E66 code indicates that the vehicle's battery charger control circuit is reading a voltage that is too low, which can affect the charging system's performance.
The P0E66 code is triggered when the Powertrain Control Module (PCM) detects a lower than expected voltage in the battery charger control circuit. This could be due to wiring issues, a faulty charger, or a malfunctioning control module.
• Battery not charging properly
• Warning light on the dashboard
• Reduced vehicle performance
• Faulty battery charger
• Damaged or corroded wiring or connectors
• Malfunctioning Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Check for any other related codes.
• Inspect wiring and connectors for damage or corrosion.
• Test the battery charger for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty battery charger.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery and charging system components.
• Keep electrical connections clean and secure.
• Perform routine maintenance checks.
Electrical Circuit Issue
• Do not ignore the warning light; get it checked promptly.
• Avoid using additional electrical accessories until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on electrical components.
This code has been more prevalent in hybrid and electric vehicles due to their complex charging systems.
Moderate – It should be addressed soon to prevent battery issues.
Ignoring this issue could lead to battery failure, which may affect vehicle safety.
• Vehicle must be in a safe, dry environment.
• Ensure the battery is fully connected.
The battery charger is typically located near the vehicle's battery or in the engine compartment.
Q: Can I drive with a P0E66 code?
A: It's not recommended to drive for long periods with this code, as it may lead to battery failure.
Q: How do I reset the P0E66 code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
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