Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with one of the car's speakers that makes noise to warn people walking nearby.
The code B0123 indicates an issue with the secondary pedestrian alert speaker, which is used to emit sound to alert pedestrians of the vehicle's presence.
The B0123 code is triggered when the vehicle's onboard diagnostic system detects a fault in the Pedestrian Alert Speaker B. This speaker is part of a system designed to produce sound to alert pedestrians, especially in electric or hybrid vehicles that may be quieter than traditional vehicles. The fault could be due to electrical issues, speaker damage, or a communication error with the control module.
• No sound from pedestrian alert system
• Warning light on dashboard
• Error message on vehicle display
• Faulty Pedestrian Alert Speaker B
• Wiring issues or loose connections
• Faulty control module
Pedestrian Alert Speaker: A device that emits sound to alert pedestrians of a vehicle's presence.
OBD-II: On-Board Diagnostics, a system that monitors vehicle performance and emissions.
• Inspect the speaker and wiring for physical damage.
• Check for loose or corroded connections.
• Use a diagnostic scanner to read any additional trouble codes.
• Replace the faulty speaker.
• Repair or replace damaged wiring.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Screwdrivers
$100 - $300
Moderate
• Toyota Prius
• Nissan Leaf
• Chevrolet Bolt
• Regularly inspect the speaker and wiring.
• Keep the vehicle's software updated.
• Avoid exposure to excessive moisture.
Sensor Issue
• Have the vehicle inspected by a professional if the warning light appears.
• Do not ignore the warning as it affects pedestrian safety.
Check with the manufacturer for warranty coverage on electronic components.
This code has become more common with the increase in hybrid and electric vehicles, which rely on pedestrian alert systems.
Moderate – It affects pedestrian safety, so it should be addressed promptly.
Ensure compliance with local regulations regarding pedestrian alert systems.
• Vehicle in a quiet environment
• Engine running
Typically located near the front of the vehicle, often integrated into the bumper area.
Q: What is a pedestrian alert speaker?
A: It's a speaker that makes noise to alert pedestrians of a vehicle's presence, especially in quieter vehicles like electric cars.
Q: Can I drive with a B0123 code?
A: Yes, but it's important to fix it soon as it affects pedestrian safety.
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