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Code B0122

Symptoms

• No sound from pedestrian alert speaker

• Warning light on the dashboard

• Error message on the vehicle's display

Common Causes

• Faulty pedestrian alert speaker

• Wiring issues or loose connections

• Faulty control module

Glossary

OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.

Control Module: A computer in the vehicle that controls various functions, including the pedestrian alert system.

Related Codes

• B0123

• B0124

Laymans terms

This code means that there's a problem with the speaker in the car that makes noise to alert people walking nearby.

Explanation

The B0122 code indicates an issue with the pedestrian alert speaker system, which is designed to make noise to warn pedestrians of the vehicle's presence, especially in electric or hybrid vehicles that are very quiet.

Technical description

The B0122 code is triggered when the vehicle's control module detects a malfunction in the pedestrian alert speaker system. This system is crucial for alerting pedestrians, especially in low-speed scenarios where the vehicle's engine noise is minimal or non-existent.

Diagnosis steps

• Inspect the pedestrian alert speaker for damage.

• Check wiring and connections to the speaker.

• Use a diagnostic tool to test the control module.

Repair procedures

• Replace the pedestrian alert speaker if faulty.

• Repair or replace damaged wiring.

• Reprogram or replace the control module if necessary.

Tools required

• OBD-II scanner

• Multimeter

• Screwdriver set

Estimated repair cost

$100 - $300

Difficulty level

Moderate

Commonly affected vehicles

• Toyota Prius

• Nissan Leaf

• Chevrolet Bolt

Preventive measures

• Regularly inspect the pedestrian alert system.

• Keep the vehicle's software updated.

• Ensure all connections are secure.

Error code type

Sensor Issue

User experience recommendations

• Have the system checked by a professional if you notice any issues.

• Do not ignore warning lights on the dashboard.

Warranty information

Check with your vehicle manufacturer to see if the pedestrian alert system is covered under warranty.

Historical data

The B0122 code has become more common with the rise of electric and hybrid vehicles, which require additional systems to alert pedestrians.

Urgency level

Moderate – While the vehicle can still be driven, the lack of pedestrian alert sound can pose a safety risk.

Legal and safety notice

Ensure the pedestrian alert system is functioning to comply with safety regulations and prevent accidents.

Testing conditions

• Vehicle at low speed.

• Quiet environment to detect sound issues.

Component location

The pedestrian alert speaker is typically located at the front of the vehicle, near the bumper.

FAQs

Q: What happens if I ignore this code?
A: Ignoring this code can lead to safety risks as pedestrians may not hear your vehicle approaching.

Q: Can I fix this issue myself?
A: If you're comfortable with car electronics, you can inspect the system, but it's best to have a professional handle repairs.

Last updated: Jun 8, 2026 • Source: internal database
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