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

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. 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 , GENERAL TROUBLESHOOTING INFORMATION , and Battery Terminal Disconnection and Reconnection (see USING THE GR8 BATTERY DIAGNOSTIC STATION ).
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 81-61 or 81-62 indicated?

YES -Go to step 6.

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. 2 (7.5 A) fuse in the auxiliary under-dash fuse holder 2.
Is the fuse OK?

YES -Go to step 6.

NO -Replace the fuse, then turn the ignition switch to ON (II). If the fuse blows again, check for short in the auxiliary under-dash fuse holder 2 No. 2 (7.5 A) fuse circuit (right engine compartment wire harness, floor wire harness, or ODS unit harness), and retest.
Check the connection between the ODS unit harness 18P connector (A) and the ODS unit (B).

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 7.

NO -Repair the poor connection and retest. If DTC 81-61 or 81-62 is still present, go to step 7.
Disconnect the ODS unit harness 18P connector (A) from the ODS unit(B).

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).
Measure the voltage between body ground and ODS unit harness 18P connector terminal No. 1.

Fig 3: Measuring Voltage Between Body Ground And ODS Unit Harness 18P Connector Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 10.

NO -Open in the right engine compartment wire harness, floor wire harness, or 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. 12.

Fig 4: Measuring Resistance Between Body Ground And ODS Unit Harness 18P Connector Terminal No. 12
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 1.0 Ω?

YES -Go to step 12.

NO -Open in the floor wire harness or ODS unit harness, or poor connection at the ODS unit harness 18P connector and the ODS unit. Check the ground connection at G605. Check the connection; if the connection is OK, replace the faulty harness, then clear the DTC.
Disconnect the negative cable from the battery, then wait at least 3 minutes.
Vehicles with ACC: Disconnect E-Pretensioner unit connector B(14P) from the E-Pretensioner unit (see E-PRETENSIONER UNIT REPLACEMENT ).
Disconnect SRS unit connector B (39P) from the SRS unit (see DISCONNECTING SYSTEM CONNECTORS ).
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 17.

NO -Short to ground between SRS unit connector B (39P) terminal No. 1 and the ODS unit harness 18P connector terminal No. 7 (right engine compartment wire harness, floor wire harness, or ODS unit harness); replace the faulty harness, then clear the DTC.
Reconnect the negative cable to the battery.
Turn the ignition switch to ON (II).
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 harness between SRS unit connector B (39P) terminal No. 1 and the ODS unit 18P connector terminal No. 7 (floor wire harness or 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. 7.

Fig 7: Measuring Resistance Between SRS Unit Connector B (39P) Terminal No. 1 And ODS Unit Harness 18P Connector Terminal No. 7
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. If the problem is still present, replace the SRS unit (see SRS UNIT REPLACEMENT ).

NO -Open in the wire harness between SRS unit connector B (39P) terminal No. 1 and ODS unit harness 18P connector terminal No. 7 (floor wire harness, or ODS unit harness); replace the faulty harness, then clear the DTC.