What this code means
This code may mean the SRS unit is seeing too much resistance or an open circuit in the front passenger side airbag inflator circuit.
What the vehicle may do
- The SRS warning light may be on.
- The airbag system may store the code as current or intermittent.
- The front passenger side airbag may not be available as intended while the fault is present.
Possible fault areas
- Possible front passenger side airbag inflator circuit concern.
- Possible open or high-resistance condition in the floor harness.
- Possible poor connection at the SRS unit connector.
- Possible SRS unit side concern or software-related issue.
Diagnostic path
Code meaning and safety setup
On this 2010 to 2016 Honda CR-V, B0028 points to an open or increased resistance condition in the front passenger's side airbag inflator circuit. The SRS warning may be on, and the system may not be able to use that side airbag as intended. The fault area can be the passenger side airbag inflator circuit, the floor harness, a connector issue at the SRS unit, or the SRS unit side of the circuit. Before touching the SRS system, find out whether the vehicle was in a collision. If it was, make sure the required SRS parts were renewed with the correct part numbers and installed properly. Also use normal SRS precautions and the correct 12 Volt Battery Terminal Disconnection and Reconnection process before unplugging anything.
First, duplicate the fault
Start by clearing the DTCs with the HDS. Turn the vehicle to the ON mode and wait for 10 seconds, then check codes again with the HDS. If B0028-13 comes right back, the failure is duplicated and you can continue into circuit testing. If it does not come back, treat it as an intermittent failure and the system is OK at that moment. If other codes are present, check what they mean first instead of chasing this circuit blindly.
Isolate the passenger side airbag inflator
For the inflator check, turn the vehicle to OFF, disconnect the negative cable from the 12 volt battery, and wait at least 3 minutes. Disconnect the front passenger's side airbag inflator 2P connector on the floor wire harness. Connect SRS simulator lead L to the SRS inflator simulator using the 2 Ω connectors, then connect lead L to that 2P connector on the floor wire harness. Reconnect the negative cable to the 12 volt battery, clear the DTCs with the HDS, turn the vehicle to ON, wait for 10 seconds, and check for B0028-13 again. If the code is gone with the simulator installed, the supported call is an open in the front passenger's side airbag inflator; replace the front passenger's side airbag, then clear the DTC. If the code is still present, keep going into the RSA＋ and RSA－ open-wire check.
Check the RSA＋ and RSA－ lines for an open
Now turn the vehicle back to OFF, disconnect the negative cable from the 12 volt battery, and wait at least 3 minutes. Disconnect SRS unit connector B, the 39P connector. Next, disconnect the SRS inflator simulator from SRS simulator lead L, but do not disconnect SRS simulator lead L from the front passenger's side airbag inflator 2P connector on the floor wire harness. With the vehicle OFF, that floor harness connector disconnected from the airbag, SRS unit connector B disconnected, and SRS simulator lead L still connected at the floor harness connector, measure resistance at the black terminal of SRS simulator lead L. The decision point is 1.0 Ω or less.
Use the resistance result to choose the fault path
If the measurement is not 1.0 Ω or less, the supported diagnosis is an open in the floor wire harness; replace the floor wire harness, then clear the DTC. If the measurement is 1.0 Ω or less, the RSA＋ and RSA－ wires are OK. At that point, focus on a poor connection at SRS unit connector B and the SRS unit, or a faulty SRS unit. Before replacing the SRS unit, check the SRS unit software version with the HDS. If it is not the latest version, update the SRS unit software and retest. If the connector-check path is not clear at this point, stop, recheck the earlier diagnostic path, and avoid guessing. If the connection is OK, the supported next step is SRS unit replacement. If the DTC still does not clear after that, the supported follow-up is floor wire harness replacement.
Verification and takeaway
Keep verification separate from the circuit test. After the supported repair, clear the DTC, turn the vehicle to ON, wait for 10 seconds, and confirm B0028-13 stays gone. The clean way through this code is to prove the fault first, isolate the airbag inflator with the simulator, then use the 1.0 Ω or less check to separate an open harness from the SRS unit side of the circuit. For more diagnostic training, visit stepdiagnostics.com.
Final check
Confirm the code first, isolate the inflator with the simulator, then use the RSA circuit resistance result to separate harness faults from the SRS unit side of the circuit.
For more guided automotive diagnostics, visit STEP Diagnostics.
