Views: 222 Author: Leah Publish Time: 2025-02-20 Origin: Site
Content Menu
● Understanding the Belt Tension Sensor (BTS)
>> Role of the Occupant Classification (OC) Module
>> Removing the Seat Belt Buckle Switch
>> Installing the Seat Belt Buckle Switch
● Passive Occupant Detecting System (PODS)
● Belt Tension Monitoring System
● Diagnostic Trouble Codes Related to SRS
● FAQ
>> 1. What does the B1495 code mean?
>> 2. Can I fix the B1495 code myself?
>> 3. How does a faulty belt tension sensor affect safety?
>> 4. What are the common causes of the B1495 code?
>> 5. How is the B1495 code diagnosed?
The B1495 diagnostic trouble code (DTC) indicates a manufacturer-specific fault related to the vehicle's body[5]. Specifically, in Hyundai and Kia vehicles, the B1495 code refers to a defect in the belt tension sensor (BTS) circuit[4][8]. The Supplemental Restraint System Control Module (SRSCM) sets this code if it detects a short to the battery line or a short to the ground between the belt tension sensor (BTS) and the Occupant Classification (OC) Module[2][4].
The belt tension sensor is a critical component of a vehicle's safety system, particularly within the supplemental restraint system (SRS)[1][8]. Its primary function is to measure the tension of the seat belt and provide this information to the SRSCM[1]. The SRSCM then uses this data to determine whether to deploy the airbags and/or pretensioners in the event of a collision[1].
The Supplemental Restraint System Control Module (SRSCM) serves mainly to differentiate between events that require restraint system deployment and those that do not. After deciding that pretensioners and/or airbag deployment are necessary, the SRSCM must provide sufficient power to the pretensioners and airbag igniters to start deployment[1].
The belt tension sensor typically consists of a sensor and related circuitry that monitors the force exerted on the seat belt[1][2][4]. This sensor is usually located within the seat belt buckle or retractor mechanism[1]. When the seat belt is buckled and tensioned, the sensor sends a signal to the SRSCM indicating the amount of tension[1].
The Occupant Classification (OC) Module uses a bladder placed between the passenger seat cushion and suspension to measure the occupant's loading force on the vehicle seat. The quantitative force determined by the system is compared to a given threshold for determination of passenger airbag suppression[1].
When the B1495 code is triggered, you may notice several symptoms:
- SRS Warning Light: The most common symptom is the illumination of the SRS warning light on the dashboard[1]. This indicates that there is a problem with the supplemental restraint system.
- Airbag Malfunction: In some cases, the airbags may not deploy properly in the event of a collision[1]. This can significantly increase the risk of injury.
- Pretensioner Malfunction: The seat belt pretensioners may also fail to activate, which can reduce the effectiveness of the seat belts in a crash[1].
- Other Codes: The B1495 code may be accompanied by other DTCs related to the SRS system[1].
Several factors can cause the B1495 code:
- Short Circuit: A short to the battery line or a short to the ground in the BTS circuit is the most common cause[2][4].
- Open Circuit: An open circuit in the BTS wiring can also trigger the code.
- Faulty Sensor: The belt tension sensor itself may be defective[1].
- Wiring Issues: Damaged, corroded, or loose wiring can cause the code.
- SRSCM Failure: In rare cases, a faulty SRSCM can cause the B1495 code[1].
Diagnosing the B1495 code requires specialized tools and knowledge. A mechanic will typically follow these steps:
1. Scan for Codes: Use an OBD-II scanner to confirm the presence of the B1495 code and check for any other related codes[1].
2. Inspect Wiring: Carefully inspect the wiring and connectors associated with the belt tension sensor for any signs of damage, corrosion, or looseness.
3. Check Sensor Resistance: Use a multimeter to measure the resistance of the belt tension sensor. Compare the reading to the manufacturer's specifications.
4. Test Sensor Signal: Use an oscilloscope to check the signal from the belt tension sensor while the seat belt is buckled and tensioned.
5. Inspect SRSCM: If the wiring and sensor appear to be in good condition, the mechanic may suspect a problem with the SRSCM. Further testing may be required.
The repair procedure for the B1495 code depends on the underlying cause. Common repairs include:
- Wiring Repair: Repairing or replacing damaged or corroded wiring and connectors[7].
- Sensor Replacement: Replacing a faulty belt tension sensor[7].
- SRSCM Replacement: Replacing a faulty SRSCM (in rare cases)[1].
The SRSCM monitors the status of the driver and front passenger seat belt buckle. The SRSCM provides one pin each for the driver and front passenger seat belt buckle status input. The seat belt buckle circuit operates from an internal boost voltage supplied by the SRSCM and uses the chassis ground for the signal return. The buckle status modifies the SRSCM deployment; if the buckle status is unbuckled, the corresponding pretensioner will be deactivated[1].
1. Disconnect the battery negative cable and wait at least three minutes before beginning work[1].
2. Remove the front seat assembly[1].
3. Loosen the seat belt buckle mounting bolt and remove the seat belt buckle switch[1].
1. Ensure the harness wires are not pinched or interfered with by other parts[1].
2. Disconnect the battery negative cable and remove the ignition key[1].
3. Install the seat belt buckle switch, tightening to a torque of 39.2 ~ 53.9 Nm[1].
4. Install the front seat assembly[1].
5. Reconnect the battery negative cable[1].
6. Confirm proper system operation by turning the ignition switch ON. The SRS indicator should turn on for about six seconds and then go off[1].
The Passive Occupant Detecting System (PODS) uses a bladder placed between the passenger seat cushion and suspension to measure the occupant's loading force on the vehicle seat. The quantitative force determined by the system is compared to a given threshold for determination of passenger airbag suppression. The system also measures dynamic responses of the occupant. However, the dynamic measurements are not intended, nor capable of monitoring the seating position of the occupant, nor can they determine the proximity of the occupant to the inflator modules[1].
1. Bladder: Senses occupant weight and provides fluid pressure input to the Pressure Sensor[1].
2. Backer Board: Provides a stable and smooth reaction surface for the Bladder, together with the Felt Pad[1].
3. Felt Pad: Provides a stable reaction surface for the Bladder, together with the Backer Board, and protects the Bladder Assembly from the seat frame environment[1].
4. Pressure Sensor: Senses pressure input from the Bladder and converts the pressure input to a voltage signal for the ECU[1].
5. ECU: Utilizes data from the Pressure Sensor, BTS (Belt Tension sensor), and Compensation Tables to determine if the Passenger Airbag will be suppressed[1].
A belt tension monitoring system can monitor belt tension in real-time. One such system includes a tensioning trolley, a three-dimensional camera, and a controller[3]. The tensioning trolley connects to the belt conveyor via the belt, and the 3D camera monitors the position change of the tensioning trolley, transmitting the 3D image data to the controller. The controller then calculates the distance between the trolley and the camera, determining if the belt tension is normal[3].
Here are some diagnostic trouble codes related to the Supplemental Restraint System (SRS)[1]:
- B1347: Driver airbag resistance too Low (1st stage)
- B1348: Driver airbag resistance circuit short to ground (1st stage)
- B1349: Driver airbag resistance circuit short to battery (1st stage)
- B1352: Passenger airbag resistance too High (1st stage)
- B1353: Passenger airbag resistance too Low (1st stage)
- B1354: Passenger airbag resistance circuit short to ground (1st stage)
- B1355: Passenger airbag resistance circuit short to battery (1st stage)
- B1361: Pretensioner front - Driver resistance too high
- B1362: Pretensioner front - Diver resistance too low
- B1363: Pretensioner front - Driver resistance circuit short to ground
- B1364: Pretensioner front - Driver resistance circuit short to battery
- B1367: Pretensioner front - Passenger resistance too high
- B1368: Pretensioner front - Passenger resistance too low
- B1369: Pretensioner front - Passenger resistance circuit short to ground
- B1370: Pretensioner front - Passenger resistance circuit short to battery
- B1378: Side airbag front - Driver resistance too high
- B1379: Side airbag front - Driver resistance too low
- B1380: Side airbag front - Driver resistance circuit short to ground
- B1381: Side airbag front - Driver resistance circuit short to battery
- B1382: Side airbag front - Passenger resistance too high
- B1383: Side airbag front - Passenger resistance too low
- B1384: Side airbag front - Passenger resistance circuit short to ground
- B1476: Inflatable Curtain airbag - Driver resistance circuit short to battery
- B1477: Inflatable Curtain airbag - Passenger resistance too high
- B1478: Inflatable Curtain airbag - Passenger resistance too low
- B1479: Inflatable Curtain airbag - Passenger resistance circuit short to ground
- B1480: Inflatable Curtain airbag - Passenger resistance circuit short to battery
- B1481: 2nd Stage Driver airbag resistance too high
- B1482: 2nd Stage Driver airbag resistance too low
- B1483: 2nd Stage Driver airbag resistance circuit short to ground
- B1484: 2nd Stage Passenger airbag resistance too high
- B1485: 2nd Stage Passenger airbag resistance too low
- B1486: 2nd Stage Passenger airbag resistance circuit short to ground
- B1489: PODS(Passenger Occupant Detecting System) ECU defect
- B1490: PODS(Passenger Occupant Detecting System) Sensor(Bladder) defect
- B1493: PODS(Passenger Occupant Detecting System) communication error
- B1494: PODS(Passenger Occupant Detecting System) wrong ID
- B1495: BTS(Belt - Tension Sensor) defect[2][4]
- B1496: PODS(Passenger Occupant Detecting System) not calibrated
- B1511: Buckle Switch Driver open or short to Battery
- B1512: Buckle Switch Driver short or short to Ground
- B1513: Buckle Switch Passenger open or short to Battery
- B1514: Buckle Switch Passenger short or short to Ground
- B1515: Buckle Switch Driver Defect (Cross Coupling)
The B1495 belt tension sensor code indicates a problem within the vehicle's supplemental restraint system. Addressing this code promptly is crucial to ensure the proper functioning of the airbags and seat belt pretensioners, which are vital for occupant safety in the event of a collision. A thorough diagnosis by a qualified mechanic is necessary to determine the root cause and perform the appropriate repairs.
The B1495 code indicates a problem with the belt tension sensor (BTS) circuit in Hyundai and Kia vehicles. It usually means there's a short or open circuit in the sensor wiring or a faulty sensor[2][4].
Due to the complexity of the SRS system, it's best to have a qualified mechanic diagnose and repair the B1495 code. Incorrect repairs can lead to airbag malfunction or accidental deployment[1].
A faulty belt tension sensor can prevent the airbags and seat belt pretensioners from deploying properly in a collision, increasing the risk of injury[1].
Common causes include a short circuit in the BTS wiring, a faulty sensor, damaged wiring, or a problem with the SRSCM[2][4].
A mechanic will use an OBD-II scanner to read the code, inspect the wiring and connectors, test the sensor resistance and signal, and possibly check the SRSCM[1].
[1] https://www.sportiveshyundai.fr/wp-content/uploads/bsk-pdf-manager/2019/09/11.0-Restraint.pdf
[2] https://www.autocodes.com/b1495_kia.html
[3] https://patents.google.com/patent/CN113998416B/en
[4] https://www.autocodes.com/b1495_hyundai.html
[5] https://dot.report/dtc/B1495
[6] https://patents.google.com/patent/CN101454184A/zh
[7] https://static.nhtsa.gov/odi/rcl/2009/RCMN-09V497-1902.pdf
[8] https://www.engine-codes.com/b1495_kia.html
