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 battery system is sending too much power. It's like when you plug in too many things into a power strip and it gets overloaded.
The P1B90 code indicates that the 14-volt power module in the vehicle is detecting higher than normal voltage or current levels, which may lead to electrical system issues.
The 14-volt power module is responsible for regulating the voltage and current supplied to various electrical components in the vehicle. When this module detects a voltage or current level that exceeds its specified limits, it triggers the P1B90 code. This can be due to a fault within the module itself or an external issue affecting the module's operation.
• Dashboard warning lights
• Electrical components not functioning properly
• Battery draining quickly
• Faulty 14-volt power module
• Wiring issues such as short circuits
• Faulty alternator or voltage regulator
OBD-II: On-Board Diagnostics, a standardized system for vehicle self-diagnosis and reporting.
Voltage Regulator: A device that maintains a constant voltage level in the electrical system.
• Check for any other related codes
• Inspect the wiring and connections to the power module
• Test the alternator and voltage regulator for proper operation
• Replace or repair the 14-volt power module
• Fix any wiring issues
• Replace the alternator or voltage regulator if necessary
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $600
Moderate
• Chevrolet Volt
• Cadillac ELR
• Chevrolet Malibu Hybrid
• Regularly inspect electrical connections
• Maintain battery health
• Avoid overloading electrical systems
Electrical System Issue
• Do not ignore warning lights on the dashboard
• Have the electrical system inspected regularly
Repairs may be covered under the vehicle's electrical system warranty if applicable.
This code has been more commonly reported in hybrid and electric vehicles due to their complex electrical systems.
Moderate – It should be addressed soon to avoid further electrical issues.
Driving with electrical system faults can lead to safety hazards. Ensure repairs are done by a qualified technician.
• Vehicle in accessory mode
• Engine running with electrical load
The 14-volt power module is typically located near the vehicle's battery or under the hood.
Q: Can I drive with a P1B90 code?
A: It's not recommended to drive for long periods with this code active, as it can lead to further electrical issues.
Q: How can I reset the P1B90 code?
A: The code can be reset using an OBD-II scanner, but it's important to fix the underlying issue first.
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