DTC B2-1x ("x" can be 0 thru 9 or A thru F): No Signal From the Rear Safing Sensor (2011 model)

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Before doing this troubleshooting procedure, find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components, of the correct part number, and that they were properly installed ( see COMPONENT REPLACEMENT/INSPECTION AFTER DEPLOYMENT ).
Before doing this troubleshooting procedure, review SRS Precautions and Procedures (see PRECAUTIONS AND PROCEDURES ), General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ), and 12 Volt Battery Terminal Disconnection and Reconnection (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest, update the SRS unit software (see SRS UNIT UPDATE ) and retest.

Clear the DTCs with the HDS (see HOW TO CLEAR DTCS ).
Turn the ignition switch to ON (II), then wait for 10 seconds.
Check for DTCs with the HDS (see HOW TO RETRIEVE DTCS ).
Is DTC B2-1x indicated?

YES -Go to step 4.

NO -Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures (see TROUBLESHOOTING INTERMITTENT FAILURES ). If another DTC is indicated, troubleshoot the DTC.
Turn the ignition switch to LOCK (0).
Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.
Check the connections between SRS unit connector B (39P) and the SRS unit, and between the floor wire harness 2P connector and the rear safing sensor (see REAR SAFING SENSOR REPLACEMENT ).
Are the connections OK?

YES -Go to step 7.

NO -Replace the floor wire harness, then clear the DTC.
Disconnect SRS unit connector B (39P) from the SRS unit (see DISCONNECTING SYSTEM CONNECTORS ).
Disconnect the floor wire harness 2P connector from the rear safing sensor (see REAR SAFING SENSOR REPLACEMENT ).
Measure the resistance between SRS unit connector B (39P) terminals No. 26 and No. 27. There should be an open circuit or at least 1 MΩ.

Fig 1: Measuring Resistance Between SRS Unit Connector B (39P) Terminals No. 26 And No. 27
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 10.

Short another wire in the floor wire harness; replace the floor wire harness, then clear the DTC.
Measure the resistance between body ground and SRS unit connector B (39P) terminals No. 26 and No. 27 individually. There should be an open circuit or at least 1 MΩ.

Fig 2: Measuring Resistance Between Body Ground And SRS Unit Connector B (39P) Terminals No. 26 And No. 27
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 11.

NO -Short to ground in the floor wire harness; replace the floor wire harness, then clear the DTC.
Reconnect the negative cable to the 12 volt battery.
Turn the ignition switch to ON (II).
Measure the voltage between body ground and SRS unit connector B (39P) terminals No. 26 and No. 27 individually. There should be less than 0.2 V.

Fig 3: Measuring Voltage Between Body Ground And SRS Unit Connector B (39P) Terminals No. 26 And No. 27
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the voltage as specified?

YES -Go to step 14.

NO -Short to power in the floor wire harness; replace the floor wire harness, then clear the DTC.
Turn the ignition switch to LOCK (0).
Connect the black terminals (A) of simulator lead L to the SRS inflator simulator (jumper connector), and then connect the SRS simulator lead L to the floor wire harness 2P connector (B).

Fig 4: Connecting SRS Inflator Simulator Leads To Floor Wire Harness 2P Connector (B)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the resistance between SRS unit connector B (39P) terminals No. 26 and No. 27. There should be less than 1.0 Ω.

Fig 5: Measuring Resistance Between SRS Unit Connector B (39P) Terminals No. 26 And No. 27
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Faulty rear safing sensor or SRS unit; replace the rear safing sensor (see REAR SAFING SENSOR REPLACEMENT ), then clear the DTC, and retest. If the DTC is still present, replace the SRS unit (see SRS UNIT REPLACEMENT ).

NO -Open in the floor wire harness; replace the floor wire harness, then clear the DTC.