DTC 21-8x ("x" can be 0 thru 9 or A thru F): Short to Power in the Driver's Seat Belt Tensioner

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.

Special Tools Required

SRS Inflator Simulator 07SAZ-TB4011A
SRS Simulator Lead K 070AZ-SNAA200

NOTE:

Before doing this troubleshooting procedure, review SRS Precautions and Procedures (see PRECAUTIONS AND PROCEDURES ), General Troubleshooting Information (see DTC (DIAGNOSTIC TROUBLE CODES) ).
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 DTC memory (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 21-8x 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).
Do the 12 volt battery terminal disconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ), then wait at least 3 minutes.
Disconnect the floor wire harness 4P connector (A) from the driver's seat belt tensioner (see step 9 ).

Fig 1: Identifying Floor Wire Harness 4P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect the SRS inflator simulator (2 Ω connectors) and simulator lead K to the floor wire harness.
Do the 12 volt battery terminal reconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
Clear the DTC memory (see HOW TO CLEAR DTCS ).
Turn the ignition switch to ON (II), then wait for 10 seconds.
Read the DTC (see HOW TO RETRIEVE DTCS ).
Is DTC 21-8x indicated?

YES -Go to step 12.

NO -Short to power in the driver's seat belt tensioner; replace the driver's seat belt (see FRONT SEAT BELT REPLACEMENT ), then clear the DTC.
Turn the ignition switch to LOCK (0).
Do the 12 volt battery terminal disconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ), then wait at least 3 minutes.
Disconnect SRS unit connector B (39P) from the SRS unit (see step 10 ).
Disconnect the simulator lead from the floor wire harness.
Do the 12 volt battery terminal reconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
Turn the ignition switch to ON (II), then wait for 10 seconds.
Measure the voltage between body ground and SRS unit connector B (39P) terminals No. 12 and No. 13, individually. There should be less than 0.2 V.

Fig 2: Measuring Voltage Between Body Ground And SRS Unit Connector B (39P) Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the voltage as specified?

YES -Faulty SRS unit or poor connection at SRS unit connector B (39P) and the SRS unit. Check the connection; if the connection is OK, replace the SRS unit (see SRS UNIT REPLACEMENT ).

NO -Short to power in the floor wire harness; replace the floor wire harness, then clear the DTC.