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 a special switch in your car that controls the high voltage battery is not connected properly. It's like a toy that won't work because the batteries aren't in place.
The P0B37 code is triggered when the vehicle's control module detects that the high voltage service disconnect is open or not properly engaged.
The high voltage service disconnect is a safety feature in hybrid and electric vehicles that allows for the disconnection of the high voltage battery from the vehicle's electrical system. This code indicates that the disconnect is open, which can prevent the vehicle from operating correctly.
• Vehicle may not start
• Warning light on the dashboard
• Reduced vehicle performance
• Faulty high voltage service disconnect
• Loose or corroded connections
• Damaged wiring or connectors
High Voltage Service Disconnect: A safety feature that allows for the disconnection of the high voltage battery from the vehicle's electrical system.
Continuity: A complete path for current flow in an electrical circuit.
• Check the high voltage service disconnect for proper engagement.
• Inspect wiring and connectors for damage or corrosion.
• Test the high voltage service disconnect switch for continuity.
• Re-engage the high voltage service disconnect properly.
• Repair or replace damaged wiring or connectors.
• Replace the high voltage service disconnect switch if faulty.
• Multimeter
• Wrench set
• Safety gloves
$100 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect the high voltage service disconnect.
• Ensure proper engagement after maintenance.
• Keep connectors clean and free of corrosion.
Electrical System Issue
• Do not attempt to drive the vehicle until the issue is resolved.
• Consult a professional mechanic for repairs.
• Regularly maintain the vehicle's electrical system.
Check with the vehicle manufacturer for warranty coverage on electrical components.
This code has become more common with the rise of hybrid and electric vehicles, as they rely on high voltage systems.
High – This issue can prevent the vehicle from operating and should be addressed immediately.
Working with high voltage systems can be dangerous. Always follow safety procedures and consult a professional.
• Vehicle in OFF position
• Battery disconnected
The high voltage service disconnect is typically located near the high voltage battery, often accessible through the trunk or under the rear seat.
Q: Can I drive with a P0B37 code?
A: No, driving with this code can be unsafe as it indicates a problem with the high voltage system.
Q: How do I reset the P0B37 code?
A: The code can be reset by fixing the underlying issue and using an OBD-II scanner, but it's important to address the root cause first.
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