B18B6

DTC Troubleshooting: B18B6, B18B7

DTC B18B6:

Lost Communication With Left BSI Radar Unit

DTC B18B7:

Lost Communication With Right BSI Radar Unit

1. Clear the DTCs with the HDS.

2. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

3. Check for DTCs with the HDS.

Is DTC B18B6 or B18B7 indicated?

YES -

Go to step 4.

NO -

Intermittent failure, the system is OK at this time. Check for loose or poor connections.

4. Check for DTCs with the HDS.

Are DTC B18B6 and B18B7 indicated?

YES -

Go to step 5.

NO -

- If only DTC B18B6 is indicated, go to step 24.
- If only DTC B18B7 is indicated, go to step 32.

5. Press the engine start/stop button to select the OFF mode.

6. Disconnect the left BSI radar unit 6P connector.

7. Press the engine start/stop button to select the ON mode.

8. Measure the voltage between left BSI radar unit 6P connector terminals No. 2 and No. 5.





Is there battery voltage?

YES -

Go to step 10.

NO -

Go to step 9.

9. Measure the voltage between left BSI radar unit 6P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Repair an open in the wire or poor ground (G701).

NO -

Repair an open in the wire between the BSI control unit and the branch of the IG1 (7.5 A) line.

10. Press the engine start/stop button to select the OFF mode.

11. Disconnect the right BSI radar unit 6P connector.

12. Disconnect the BSI control unit 16P connector.

13. Check for continuity between BSI control unit 16P connector terminal No. 2 and body ground.





Is there continuity?

YES -

Repair a short to ground in the wire between the BSI control unit and the branch of the BSI-CAN line (BSI-CAN L).

NO -

Go to step 14.

14. Press the engine start/stop button to select the ON mode.

15. Measure the voltage between BSI control unit 16P connector terminal No. 3 and body ground. There should be less than 0.2 V.





Is the voltage as specified?

YES -

Go to step 16.

NO -

Repair a short to power in the wire between the BSI control unit and the branch of the BSI-CAN line (BSI-CAN H).

16. Press the engine start/stop button to select the OFF mode.

17. Check for continuity between BSI control unit 16P connector terminal No. 3 and left BSI radar unit 6P connector terminal No. 3, and between BSI control unit 16P connector terminal No. 2 and left BSI radar unit 6P connector terminal No. 1.





Is there continuity?

YES -

Go to step 18.

NO -

Repair an open in the wire between the BSI control unit and the branch of the BSI-CAN line (BSI-CAN H, BSI-CAN L).

18. Reconnect the right BSI radar unit 6P connector.

19. Reconnect the BSI control unit 16P connector.

20. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

21. Clear the DTCs with the HDS.

22. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

23. Check for DTCs with the HDS.

Are DTC B18B6 and B18B7 indicated?

YES -

Replace the right BSI radar unit BSI Radar Unit Removal/Installation.

NO -

Replace the left BSI radar unit BSI Radar Unit Removal/Installation.

24. Press the engine start/stop button to select the OFF mode.

25. Disconnect the left BSI radar unit 6P connector.

26. Press the engine start/stop button to select the ON mode.

27. Measure the voltage between left BSI radar unit 6P connector terminals No. 2 and No. 5.





Is there battery voltage?

YES -

Go to step 28.

NO -

Go to step 31.

28. Press the engine start/stop button to select the OFF mode.

29. Disconnect the BSI control unit 16P connector.

30. Check for continuity between BSI control unit 16P connector terminal No. 3 and left BSI radar unit 6P connector terminal No. 3, and between BSI control unit 16P connector terminal No. 2 and left BSI radar unit 6P connector terminal No. 1.





Is there continuity?

YES -

Replace the left BSI radar unit BSI Radar Unit Removal/Installation.

NO -

Repair an open in the wire between the BSI control unit and the left BSI radar unit.

31. Measure the voltage between left BSI radar unit 6P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Repair an open in the wire between the left BSI radar unit and ground (G701).

NO -

Repair an open in the wire between the driver's under-dash fuse/relay box and the left BSI radar unit.

32. Press the engine start/stop button to select the OFF mode.

33. Disconnect the right BSI radar unit 6P connector.

34. Press the engine start/stop button to select the ON mode, then wait for 10 seconds.

35. Measure the voltage between right BSI radar unit 6P connector terminals No. 2 and No. 5.





Is there battery voltage?

YES -

Go to step 36.

NO -

Go to step 40.

36. Press the engine start/stop button to select the OFF mode.

37. Measure the resistance between body ground and right BSI radar unit 6P connector terminals No. 4 and No. 6 individually. There should be less than 1.0 Ohms.





Is the resistance as specified?

YES -

Go to step 38.

NO -

Repair an open in the wire between the right BSI radar unit and ground (G701).

38. Disconnect the BSI control unit 16P connector.

39. Check for continuity between BSI control unit 16P connector terminal No. 3 and right BSI radar unit 6P connector terminal No. 3, and between BSI control unit 16P connector terminal No. 2 and right BSI radar unit 6P connector terminal No. 1.





Is there continuity?

YES -

Replace the right BSI radar unit BSI Radar Unit Removal/Installation.

NO -

Repair an open in the wire between the BSI control unit and the right BSI radar unit.

40. Measure the voltage between right BSI radar unit 6P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Repair an open in the wire between the right BSI radar unit and ground (G701).

NO -

Repair an open in the wire between the driver's under-dash fuse/relay box and the right BSI radar unit.