DTC 85-61: No Signal From the OPDS Unit ('04-05 models); DTC 85-62: Response Data Error From the OPDS Unit ('04-05 models)

NOTE:

An incorrect OPDS unit can cause DTC 85-63.
A new (uninitialized) OPDS unit installed with a faulty sensor can also cause DTC 85-71.
Before doing this troubleshooting procedure, review SRS Precautions and Procedures (see PRECAUTIONS AND PROCEDURES ) and General Troubleshooting Information (see DTC (DIAGNOSTIC TROUBLE CODES) ).

Make sure nothing is on the front passenger's seat.
Clear the DTC memory (see CLEAR THE DTC MEMORY WITH THE HDS ).
Read the DTC (see DTC (DIAGNOSTIC TROUBLE CODES) ).
Is DTC 85-61 or 85-62 indicated?

YES -Go to step 4.

NO -Intermittent failure, system is OK at this time. Go to TROUBLESHOOTING INTERMITTENT FAILURES . If another DTC is indicated, troubleshoot the DTC.
Check the connection between OPDS unit harness 8P connector D and the OPDS unit.
Is the connection OK?

YES -Go to step 5.

NO -Repair the poor connection and retest. If DTC 85-61 or 85-62 is still present, go to step 5.
Turn the ignition switch OFF.
Check the No. 10 (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 ON (II). If the fuse blows again, check for a short in the No. 10 (7.5 A) fuse circuit (dashboard wire harness, floor wire harness, or OPDS unit harness).
Disconnect OPDS unit 8P connector D from the OPDS unit.

Fig 1: Identifying OPDS Unit 8P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch ON (II).
Measure the voltage between the No. 4 terminal of OPDS unit 8P connector D and body ground. There should be battery voltage.

Fig 2: Measuring Voltage Between No. 4 Terminal Of OPDS Unit 8P Connector D And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 14.

NO -Go to step 10.
Turn the ignition switch OFF.
Disconnect dashboard wire harness 24P connector C501 (A) from the floor wire harness C501 (B).

Fig 3: Identifying Dashboard Wire Harness 24P Connector C501 And Floor Wire Harness C501
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch ON (II).
Measure the voltage between the No. 19 terminal of dashboard wire harness 24P connector and body ground. There should be battery voltage.

Fig 4: Measuring Voltage Between No. 19 Terminal Of Dashboard Wire Harness 24P Connector And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Open in the WHT wire of the floor wire harness or OPDS unit harness; replace the faulty harness.

NO -Open in the WHT wire of the dashboard wire harness; replace the dashboard wire harness.
Turn the ignition switch OFF.
Measure the resistance between the No. 8 terminal of OPDS unit 8P connector D and body ground. There should be 0-1.0 Ω.

Fig 5: Measuring Resistance Between No. 8 Terminal Of OPDS Unit 8P Connector D And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 16.

NO -Open in the OPDS unit harness or floor wire harness; check the connection at G602 (see FLOOR WIRE HARNESS (RIGHT BRANCH) ). If the connection is OK, replace the faulty harness.
Turn the ignition switch OFF. Disconnect the negative cable from the battery, then wait for 3 minutes.
Disconnect both seat belt tensioner 4P connectors (see step 6 ).
Disconnect SRS unit connector B (28P) from the SRS unit (see step 7 ).
Measure the resistance between the No. 27 terminal of SRS unit connector B (28P) and body ground. There should be an open circuit or at least 1 MΩ.

Fig 6: Measuring Resistance Between No. 27 Terminal Of SRS Unit Connector B (28P) And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 20.

NO -Go to step 23.
Measure the resistance between the No. 27 terminal of SRS unit connector B (28P) and the No. 7 terminal of OPDS unit 8P connector D. There should be 0-1.0 Ω.

Fig 7: Measuring Resistance Between No. 27 Terminal Of SRS Unit Connector B (28P) And No. 7 Terminal Of OPDS Unit 8P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Faulty OPDS unit or SRS unit; replace the OPDS unit (see OPDS/ODS UNIT REPLACEMENT ). If the problem is still present, replace the OPDS sensor/seat-back (see FRONT SEAT COVER REPLACEMENT ). If problem is still present, replace the SRS unit (see SRS UNIT REPLACEMENT ).

NO -Go to step 21.
Disconnect the floor wire harness 4P connector C801 from the OPDS unit harness.

Fig 8: Identifying Floor Wire Harness 4P Connector C801
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the resistance between the No. 27 terminal of SRS unit connector B (28P) and the No. 4 terminal of floor wire harness 4P connector C801. There should be 0-1.0 Ω.

Fig 9: Measuring Resistance Between SRS Unit Connector B (28P) And Floor Wire Harness 4P Connector C801
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Open in the OPDS unit harness; replace the OPDS unit harness.

NO -Open in the dashboard wire harness or floor wire harness; replace the faulty harness.
Disconnect floor wire harness 4P connector C801 from the OPDS unit harness.

Fig 10: Identifying Floor Wire Harness 4P Connector C801
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the resistance between the No. 27 terminal of SRS unit connector B (28P) and body ground. There should be an open circuit or at least 1 MΩ.

Fig 11: Measuring Resistance Between No. 27 Terminal Of SRS Unit Connector B (28P) And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Short to ground in the OPDS unit harness; replace the OPDS unit harness.

NO -Short to ground in the dashboard wire harness or floor wire harness; replace the faulty harness.