B0055 Second Row Right Seat Belt Sensor Fault

The B0055 Second Row Right Seat Belt Sensor Fault diagnostic trouble code indicates that the vehicle’s Supplemental Restraint System (SRS) or restraint control module has detected an abnormal condition involving the right-side seat belt sensor in the second row.

The second-row right seat belt sensor is part of the vehicle’s safety restraint monitoring system. Depending on the manufacturer and vehicle configuration, the sensor may be integrated into the seat belt buckle or connected to a dedicated restraint-system circuit.

The system uses this information to determine whether the seat belt is buckled and may use the signal for:

• Seat belt warning functions

• Passenger safety monitoring

• SRS diagnostics

• Occupant-restraint strategies

• Other manufacturer-specific safety functions

When the restraint control module receives a missing, incorrect, intermittent, or out-of-range signal from the second-row right seat belt sensor circuit, it can store B0055.

---

What Does B0055 Mean?

B0055 generally identifies a problem involving the second-row right seat belt sensing circuit.

The restraint control module expects to receive a specific electrical signal based on the condition of the seat belt buckle.

A simplified operation is:

1. The second-row right seat belt is unbuckled.

2. The buckle sensor sends the corresponding electrical signal.

3. The seat belt is inserted into the buckle.

4. The sensor changes its electrical state.

5. The restraint control module detects the new signal.

6. The vehicle updates the seat belt status.

If the sensor signal is missing, intermittent, incorrect, or inconsistent with the expected condition, the module may store B0055.

Possible causes include:

• Faulty seat belt buckle sensor

• Internal buckle switch failure

• Open circuit

• Short circuit

• High circuit resistance

• Damaged wiring

• Loose connector

• Corroded terminals

• Damaged buckle assembly

• Restraint control module fault

---

What Is the Second-Row Right Seat Belt Sensor?

The second-row right seat belt sensor is associated with the right-side seating position in the vehicle's second row.

Depending on the vehicle, the second row may include:

• A rear bench seat

• Individual captain's chairs

• A three-passenger bench

The sensor may be located inside or directly connected to the right-side seat belt buckle assembly.

Its primary purpose is to provide information about whether the seat belt is:

• Buckled

• Unbuckled

The control module uses this information to monitor the safety restraint system.

---

Why Is the Second-Row Right Seat Belt Sensor Important?

Seat belt status monitoring is an important part of modern vehicle safety systems.

A faulty sensor may prevent the vehicle from correctly recognizing the condition of the seat belt.

Depending on the vehicle's system design, this can affect:

• Seat belt reminder operation

• Passenger monitoring

• SRS diagnostics

• Occupant restraint monitoring

• Seat belt pretensioner monitoring

B0055 does not automatically mean that the seat belt pretensioner or airbag has failed. However, it indicates that the restraint system has detected a problem that should be properly diagnosed.

---

Symptoms of B0055

The symptoms can vary depending on the vehicle and the exact nature of the fault.

Airbag or SRS Warning Light

The airbag or SRS warning light may illuminate.

Seat Belt Warning

The vehicle may display a warning relating to the second-row right seating position.

Incorrect Unbuckled Warning

The vehicle may indicate that the seat belt is unbuckled even when it is correctly fastened.

Incorrect Buckled Status

The system may incorrectly recognize the seat belt as fastened.

Warning Chime

The seat belt warning chime may operate incorrectly.

Intermittent Warning Light

A loose connector or damaged wire may cause the warning light to appear intermittently.

No Noticeable Driving Problems

Because B0055 is a body and restraint-system code, the vehicle may otherwise drive normally.

---

Common Causes of B0055

Several electrical and mechanical problems can trigger the B0055 code.

Faulty Right Seat Belt Buckle Sensor

The internal buckle sensor may fail because of:

• Normal wear

• Electrical failure

• Internal contamination

• Damaged contacts

• Mechanical buckle failure

---

Damaged Seat Belt Buckle

Physical damage can prevent the internal sensor or switch from operating correctly.

Possible causes include:

• Foreign objects inside the buckle

• Dirt or debris

• Excessive force

• Liquid contamination

• Mechanical damage

---

Damaged Wiring

The second-row seat belt wiring can be damaged because of:

• Seat movement

• Folding seats

• Sliding seats

• Passenger contact

• Cargo

• Previous repairs

Possible wiring problems include:

• Pinched wires

• Broken wires

• Chafed insulation

• Open circuits

• Short circuits

• Excessive circuit resistance

---

Loose Electrical Connector

A connector may become loose after:

• Seat removal

• Interior repairs

• Carpet replacement

• Seat movement

• Electrical modifications

---

Corroded Terminals

Moisture can cause:

• Corroded terminals

• Increased electrical resistance

• Intermittent signals

• Poor electrical contact

---

Previous Seat or Interior Repairs

B0055 may appear after work involving:

• Seat removal

• Seat replacement

• Carpet installation

• Interior trim removal

• Audio-system installation

• Electrical modifications

---

Restraint Control Module Fault

A control-module problem is possible but is generally less common than a sensor or wiring fault.

The sensor, buckle, wiring, and connectors should normally be checked first.

---

Vehicles Commonly Affected by B0055

B0055 can occur on vehicles equipped with electronically monitored second-row seat belts.

Examples can include:

• Chevrolet Tahoe

• Chevrolet Suburban

• GMC Yukon

• Cadillac Escalade

• Ford Expedition

• Ford Explorer

• Lincoln Navigator

• Toyota Sequoia

• Toyota Highlander

• Nissan Armada

• Nissan Pathfinder

• Infiniti QX80

• Jeep Grand Cherokee L

• Dodge Durango

• Volkswagen Atlas

• Audi Q7

• Volvo XC90

• Mercedes-Benz GLS

• BMW X7

• Kia Telluride

• Hyundai Palisade

This is not a complete application list.

The exact definition of B0055 can vary according to the manufacturer, model year, restraint control module, and seat belt system configuration. Vehicle-specific diagnostic information should be used to identify the exact affected component.

---

How B0055 Is Diagnosed

B0055 should be diagnosed using an SRS/airbag-capable diagnostic scanner.

A basic engine-code scanner may not be able to communicate with the restraint control module.

Scan the SRS Module

Retrieve:

• Current codes

• Stored codes

• History codes

• Manufacturer-specific subfaults

• Related SRS codes

Additional codes can help determine whether B0055 is an isolated seat belt sensor problem.

---

Inspect the Second-Row Right Seat Belt Buckle

Check the buckle and surrounding area for:

• Physical damage

• Foreign objects

• Dirt or contamination

• Loose mounting

• Mechanical latch problems

The seat belt should latch and release normally.

---

Inspect the Wiring Harness

The wiring leading to the second-row right seat belt should be inspected for:

• Pinched wires

• Broken conductors

• Chafed insulation

• Exposed wiring

• Incorrect previous repairs

• Damage caused by seat movement

---

Inspect the Electrical Connector

Check the connector for:

• Loose connections

• Corrosion

• Bent terminals

• Water intrusion

• Damaged connector locks

A connector can appear properly connected while still having poor terminal contact.

---

Check the Sensor Circuit

Following the manufacturer’s diagnostic procedure, technicians may test:

• Circuit continuity

• Circuit resistance

• Short-to-ground conditions

• Short-to-power conditions

• Sensor signal voltage

The correct procedure depends on the vehicle.

Important: Some SRS-related circuits are associated with pyrotechnic components, including seat belt pretensioners. Always follow the manufacturer's specified safety procedure before disconnecting or testing restraint-system components.

---

Monitor Live SRS Data

If supported by the diagnostic tool, technicians can monitor the second-row right seat belt status.

The live data should change correctly when the seat belt is:

• Buckled

• Unbuckled

If the status does not change despite normal buckle operation, the sensor or its circuit may be faulty.

---

How to Fix B0055

The correct repair depends on the confirmed cause.

Repair Damaged Wiring

Possible repairs include:

• Repair broken wires

• Replace damaged harness sections

• Repair pinched wiring

• Restore damaged insulation

• Secure the harness away from moving seat components

---

Repair or Replace the Connector

Connector repairs may include:

• Replacing damaged terminals

• Replacing the connector housing

• Correcting terminal tension

• Cleaning corrosion where appropriate

---

Replace the Seat Belt Buckle or Sensor

If testing confirms that the second-row right seat belt sensor or buckle switch is defective, the affected component may need replacement.

On many vehicles, the sensor is integrated into the seat belt buckle and is not separately serviceable.

---

Repair or Replace the Restraint Control Module

If the sensor, wiring, and connectors test correctly, the restraint control module may require further diagnosis.

Depending on the vehicle, this may involve:

• Software programming

• Module configuration

• Professional module repair

• Module replacement

---

What to Do After Repairing B0055

After completing the repair:

1. Follow the manufacturer's SRS safety procedure.

2. Clear the B0055 diagnostic trouble code.

3. Monitor the second-row right seat belt status with the scan tool.

4. Buckle and unbuckle the seat belt to verify signal changes.

5. Confirm that the airbag/SRS warning light remains off.

6. Perform a complete SRS diagnostic scan.

7. Verify that no related restraint-system codes remain.

---

Can You Drive With B0055?

The vehicle may continue to operate normally because B0055 does not usually affect:

• Engine operation

• Transmission operation

• Basic steering

• Normal braking

However, B0055 should not be ignored because it involves the vehicle's safety restraint system.

If the SRS warning light is illuminated, the correct operation of all affected restraint functions should not be assumed until the fault has been diagnosed and repaired.

---

Is B0055 a Serious Code?

B0055 should be considered an important safety-related diagnostic trouble code.

Although the vehicle may continue to drive normally, the code can affect safety-system monitoring.

Potentially affected functions include:

• Seat belt status monitoring

• Seat belt warning systems

• Passenger monitoring

• SRS diagnostics

• Pretensioner monitoring

An illuminated airbag or SRS warning light should always be investigated.

---

How to Prevent B0055

Recommended practices include:

• Avoid damaging wiring underneath second-row seats.

• Inspect the wiring after moving, folding, or removing seats.

• Keep electrical connectors dry.

• Do not modify SRS wiring.

• Repair damaged seat belt components promptly.

• Keep the buckle free from dirt and foreign objects.

• Avoid forcing or twisting the seat belt buckle.

• Address SRS warning lights promptly.

• Follow manufacturer procedures during seat and interior repairs.

---

B0055 vs. Other Related Seat Belt Codes

B0055 belongs to a broader group of restraint-system diagnostic codes.

Code	Description
B0055	Second Row Right Seat Belt Sensor Fault
B0056	Third Row Left Seat Belt Sensor Fault
B0057	Third Row Center Seat Belt Sensor Fault
B0058	Third Row Right Seat Belt Sensor Fault

The exact definitions and code assignments can vary between manufacturers. Vehicle-specific service information should always take priority during diagnosis.

---

Final Thoughts

The B0055 Second Row Right Seat Belt Sensor Fault diagnostic trouble code indicates that the vehicle's restraint control system has detected an abnormal condition involving the right-side seat belt sensor in the second row.

Common causes include:

• Faulty seat belt buckle sensor

• Defective internal buckle switch

• Damaged wiring

• Pinched harness

• Loose connector

• Corroded terminals

• Physical buckle damage

• Previous seat or interior repairs

• Restraint control module problems

The best diagnostic approach is to scan the SRS module, inspect the second-row right seat belt buckle, check the wiring and connectors, monitor live seat belt data, and test the sensor circuit according to the manufacturer’s procedure.

Because this is a safety restraint-system fault, B0055 should be diagnosed and repaired rather than simply clearing the code. Any work involving SRS components should follow the manufacturer's specified safety procedures.