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

Special Tools Required

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

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 DTC (DIAGNOSTIC TROUBLE CODES) ), 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 CLEAR 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 . 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.
Remove the left rear side trim panel (see TRIM REMOVAL/INSTALLATION - CARGO AREA ).
Disconnect the driver's seat belt tensioner 4P connector (A) on the floor wire harness.

Fig 1: Disconnecting Driver's Seat Belt Tensioner 4P Connector On Floor Wire Harness
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect the terminals of SRS simulator lead K to the SRS inflator simulator (2 Ω connectors), and then connect the SRS simulator lead K to the driver's seat belt tensioner 4P connector on the floor wire harness.
Reconnect the negative cable to the 12 volt battery.
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 CLEAR DTCS ).
Is DTC 21-8x indicated?

YES -Go to step 13.

NO -Short to power in the driver's seat belt tensioner; replace the driver's seat belt (see SEAT BELT REPLACEMENT ), then clear the DTC.
Turn the ignition switch to LOCK (0).
Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.
Disconnect SRS unit connector B (39P) from the SRS unit (see step 10 ).
Disconnect the SRS simulator lead K from the driver's seat belt tensioner 4P connector on the floor wire harness.
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. 38 and No. 39 individually.

Fig 2: Measuring Voltage Between Body Ground And SRS Unit Connector B (39P) Terminals No. 38 And 39
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2 V?

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 ). If the DTC does not clear, replace the floor wire harness.

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