DTC 81-61: No Signal From the ODS Unit; DTC 81-62: Incorrect Data From the ODS Unit

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.

Make sure nothing is on the front passenger's seat.
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 81-61 or 81-62 indicated?

YES -Go to step 5.

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).
Check the No. B8 (7.5 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?

YES -Go to step 7.

NO -Replace the fuse, then turn the ignition switch to ON (II). If the fuse blows again, check for a short in the No. B8 (7.5 A) fuse circuit (dashboard wire harness, floor wire harness, or ODS unit harness); replace the faulty harness, then clear the DTC.
Check the connection between the ODS unit harness 18P connector (A) and the ODS unit.

Fig 1: Identifying ODS Unit Harness 18P Connector And ODS Unit
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the connection OK?

YES -Go to step 8.

NO -Repair the poor connection, then clear the DTC, and retest. If DTC 81-61 or 81-62 is still present, go to step 8.
Disconnect the ODS unit harness 18P connector (A) from the ODS unit.

Fig 2: Identifying ODS Unit Harness 18P Connector And ODS Unit
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch to ON (II), then wait for 10 seconds.
Measure the voltage between body ground and ODS unit harness 18P connector terminal No. 7.

Fig 3: Measuring Voltage Between Body Ground And ODS Unit Harness 18P Connector Terminal No. 7
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 11.

NO -Open in the dashboard wire harness, the floor wire harness, or the ODS unit harness; replace the faulty harness, then clear the DTC.
Turn the ignition switch to LOCK (0).
Measure the resistance between body ground and ODS unit harness 18P connector terminal No. 18.

Fig 4: Measuring Resistance Between Body Ground And ODS Unit Harness 18P Connector Terminal No. 18
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 1.0 Ω?

YES -Go to step 13.

NO -Open in the floor wire harness or the ODS unit harness, or a poor connection at the ODS unit harness 18P connector and the ODS unit. Check the ground connection at G601 (see FLOOR WIRE HARNESS (SA) ). Check the connection; if the connection is OK, replace the faulty harness, then clear the DTC.
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 ).
Measure the resistance between body ground and SRS unit connector B (39P) terminal No. 1.

Fig 5: Measuring Resistance Between Body Ground And SRS Unit Connector B (39P) Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there an open circuit or at least 1 MΩ?

YES -Go to step 16.

NO -Short to ground or to another wire in the floor wire harness or the ODS unit harness; replace the faulty harness, then clear the DTC.
Reconnect the negative cable to the 12 volt battery.
Turn the ignition switch to ON (II), then wait for 10 seconds.
Measure the voltage between body ground and SRS unit connector B (39P) terminal No. 1.

Fig 6: Measuring Voltage Between Body Ground And SRS Unit Connector B (39P) Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2 V?

YES -Go to step 19.

NO -Short to power in the floor wire harness or the ODS unit harness; replace the faulty harness, then clear the DTC.
Turn the ignition switch to LOCK (0).
Measure the resistance between SRS unit connector B (39P) terminal No. 1 and ODS unit harness 18P connector terminal No. 1.

Fig 7: Measuring Resistance Between SRS Unit Connector B (39P) Terminal No. 1 And ODS Unit Harness 18P Connector Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 1.0 Ω?

YES -Faulty ODS unit or SRS unit; replace the ODS unit (see ODS UNIT 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 or ODS unit harness; replace the faulty harness, then clear the DTC.