The B0028: Passenger Side Deployment Loop Resistance Low is an issue within the passenger-side airbag system, specifically pointing to low resistance in the deployment loop.
This condition suggests that the electrical path necessary for the airbag to deploy in a collision is not as it should be, potentially due to damaged wiring or faulty connections. It’s a critical safety concern because it affects the airbag’s ability to function correctly during an accident, putting the passenger at risk.
B0028 quick overview
| Meaning | B0028: Passenger Side Deployment Loop Resistance Low |
| Is it serious? | Absolutely, as it concerns the airbag system’s readiness to deploy in a crash. |
| Possible causes | – Damaged wiring or connectors – Faulty passenger side airbag module – Corrosion in the wiring harness – Poor connections at in-line connectors |
| How to diagnose? | Inspect wiring harness for damage, corrosion, or poor connections. Perform resistance testing on the deployment loop to identify anomalies. Check for pinched or frayed wires, especially in areas prone to damage. Use a diagnostic scan tool to request SIR (Supplemental Inflatable Restraint) DTC (Diagnostic Trouble Code) display. Replace faulty components as necessary and verify proper mounting and connection integrity. |
B0028 Meaning
The B0028 code essentially means there’s a problem with the electrical system that tells the passenger’s airbag to inflate during a crash. The “low resistance” part of the code suggests that something in the wiring is not as resistant as it should be, which could be due to a wire being cut, pinched, or not properly connected.
This problem needs fixing because it could prevent the airbag from deploying when you need it most, like in an accident. Mechanics will look for and fix any issues in the wiring or replace parts of the airbag system if needed to make sure everything’s ready to work in an emergency.
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How to fix B0028 – learn from mechanics
I looked into B0028 service cases at iatn.com website where in the private forums the mechanics seek advice from other mechanics. I looked up a bunch of cases to help you decide how to fix your issue and see what would a real mechanic do to solve it.
Case #1: GMC B0028
Vehicle information 2000 GMC Yukon SLT 5.3L
Issue + repair history
- Error codes: B0028 (R/F Passenger Side Deployment Loop Resistance Low) and B0040 (L/F Side Deployment Resistance Low) were set immediately.
- Checking resistance at seat connectors reveals 0.3 Ohms on both sides.
- No signs of collision repair or water damage.
- Limited history as the vehicle was purchased from an auction in Idaho.
Other OBD2 Codes + Test Results
- No additional OBD2 codes mentioned.
- Resistance readings at R/S and L/S inflate sensors: 0.3 Ohms.
Mechanic suggestions
- Inspect wiring harness side of in-line connectors for corrosion, terminal damage, or poor connections.
- Repair or replace wiring harness if any issues are found.
- Use scan tool to request SIR DTC display and diagnose based on the results.
- Replace RF inflatable restraint side impact module if necessary.
- Verify proper mounting of all components, connectors, and CPAs after repairs.
Final fix
- Repaired wiring harness
Case #2: Ford B0028
Vehicle information 2015 Ford Fusion SE 2.5L
Issue + repair history
- Error code: B0028 (Passenger Side Deployment Loop Resistance Low) detected.
- Vehicle history indicates no prior accidents or repairs.
- Owner reported intermittent airbag warning light.
Other OBD2 Codes + Test Results
- No additional OBD2 codes mentioned.
- Live data shows normal voltage readings from airbag sensors.
- Visual inspection of connectors reveals no obvious issues.
Mechanic suggestions
- Check wiring harness integrity from passenger side airbag to control module.
- Perform resistance testing on passenger side deployment loop.
- Inspect passenger seat for any signs of wiring damage or loose connections.
- Use specialized diagnostic tools to pinpoint exact location of resistance issue.
Final fix
- Upon thorough inspection, a damaged wire in the passenger side deployment loop was discovered.
- The damaged wire was repaired, restoring proper resistance and eliminating the B0028 error code.
Case #3: Toyota B0028
Vehicle information 2012 Toyota Camry LE 2.5L
Issue + repair history
- Error code: B0028 (Passenger Side Deployment Loop Resistance Low) detected.
- Vehicle recently underwent collision repair on the passenger side.
- Owner reported airbag warning light illuminated constantly.
Other OBD2 Codes + Test Results
- No additional OBD2 codes mentioned.
- Live data indicates irregular voltage readings from passenger side airbag system.
- Post-repair inspection reveals potential damage to wiring harness in passenger side door panel area.
Mechanic suggestions
- Conduct thorough visual inspection of wiring harness in passenger side door panel.
- Check for any signs of pinched or frayed wires.
- Perform resistance testing on passenger side deployment loop.
- Ensure all connectors are properly seated and undamaged.
Final fix
- During inspection, a pinched wire was found in the wiring harness near the passenger side door panel.
- The pinched wire was repaired, restoring proper resistance in the deployment loop and resolving the B0028 error code.
How to diagnose B0028
I made you an overview of solving this DTC, based on all the advice that was suggested by certified mechanics to address this issue in previously mentioned service cases.
| Diagnostic Step | Explanation |
|---|---|
| Inspect wiring harness and connectors | Look for signs of corrosion, damage, or poor connections that could lower resistance. |
| Perform resistance testing | Use specialized tools to measure resistance levels and identify where the issue lies. |
| Check for pinched or frayed wires | Especially in areas recently repaired or prone to damage, like door panels. |
| Use a scan tool for SIR DTC display | Helps in diagnosing issues by showing specific faults in the airbag system. |
| Repair or replace damaged components | Address identified issues by repairing wiring or replacing faulty modules to restore proper function. |
| Ensure proper mounting and connection integrity | After repairs, verify that all components are securely fastened and correctly connected. |
These diagnostic steps, derived from actual service cases, emphasize the importance of a thorough inspection and precise repair to ensure the safety of vehicle occupants. Given the complexity and safety implications of airbag system repairs, seeking professional assistance is highly recommended for addressing the B0028 code.
Car Diagnostics Training
- Car Electrical basics
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I test OBD-II scanners and make DIY Engine diagnostics guides to help you solve your car problems without having to depend on the mechanic. A lot of them will try to scam you or are just no help at all. About Juraj Lukacko