B1775

DTC Troubleshooting: B1775

DTC B1775:

Microphone Input/Output Shorted to Power or Open

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Connect the HDS to the DLC.

2. Clear the DTCs with the HDS.

3. Turn the ignition switch to LOCK (0) and then back to ON (II).

4. Check for DTCs with the HDS.

Is DTC B1775 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time.

5. Turn the ignition switch to LOCK (0).

6. Disconnect the front HFL-navigation-ANC/active sound control microphone 7P connector or the front HFL-ANC/active sound control microphone 7P connector.

7. Disconnect the HandsFreeLink control unit 28P connector.

8. Turn the ignition switch to ON (II).

9. Measure the voltage between HandsFreeLink control unit 28P connector terminal No. 2 and body ground.





Is there voltage?

YES -

There is a short to power in the wire the HandsFreeLink control unit and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone. Replace the affected shielded harness.

NO -

Go to step 10.

10. Turn the ignition switch to LOCK (0).

11. Check for continuity between HandsFreeLink control unit 28P connector terminals No. 1 and No. 2 and front HFL-navigation-ANC/active sound control microphone 7P connector or front HFL-ANC/active sound control microphone 7P connector terminals No. 6 and No. 5 respectively.





Is there continuity?

YES -

- With navigation, go to step 12.
- Without navigation, substitute a known-good front HFL-ANC/active sound control microphone Front HFL-ANC/Active Sound Control Microphone Removal / Installation, and recheck. If the symptom/indication goes away, replace the original front HFL-ANC/active sound control microphone Front HFL-ANC/Active Sound Control Microphone Removal / Installation. If the symptom/indication is still present, replace the HandsFreeLink control unit Service and Repair.

NO -

There is an open in the wire between the HandsFreeLink control unit and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone. Replace the affected shielded harness.

12. Disconnect navigation unit connector C (16P).

13. Turn the ignition switch to ON (II).

14. Measure the voltage between HandsFreeLink control unit 28P connector terminal No. 16 and body ground.





Is there voltage?

YES -

There is a short to power in the wire between the HandsFreeLink control unit and the navigation unit. Replace the affected shielded harness.

NO -

Go to step 15.

15. Turn the ignition switch to LOCK (0).

16. Reconnect the HandsFreeLink control unit 28P connector and the front HFL-navigation-ANC/active sound control microphone 7P connector.

17. Turn the ignition switch to ON (II).

18. Do the HFL Self-Diagnostic Function.

Do you hear the message "The hands free system is OK"?

YES -

Replace the navigation unit Service and Repair.

NO -

Substitute a known-good front HFL-navigation-ANC/active sound control microphone Front HFL-Navigation-ANC/Active Sound Control Microphone Removal / Installation, and recheck. If the symptom/indication goes away, replace the original front HFL-navigation-ANC/active sound control microphone Front HFL-Navigation-ANC/Active Sound Control Microphone Removal / Installation. If the symptom/indication is still present, replace the HandsFreeLink control unit Service and Repair.