48-1x

SRS DTC Troubleshooting: 43-1x, 46-1x, 48-1x

DTC 43-1x ("x" can be 0 thru 9 or A thru F):

No Signal From the Left Side Impact Sensor (first)

DTC 46-1x ("x" can be 0 thru 9 or A thru F):

No Signal From the Right Side Impact Sensor (second)

DTC 48-1x ("x" can be 0 thru 9 or A thru F):

No Signal From the Right Side Impact Sensor (third)

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 Service and Repair.
- Before doing this troubleshooting procedure, review SRS Precautions and Procedures Service and Repair, General Troubleshooting Information Reading and Clearing Diagnostic Trouble Codes, and Battery Terminal Disconnection and Reconnection 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 Testing and Inspection, and retest.

1. Clear the DTC memory.

2. Turn the ignition switch to ON (II), then wait for 10 seconds.

3. Read the DTC.

Is DTC 43-xx (except 43-11) indicated?

YES -

Faulty left side impact sensor (first); replace the left side impact sensor (first) Side Impact Sensor (First) Replacement, then clear the DTC.

NO -

Go to step 4.

4. Read the DTC.

Is DTC 46-xx (except 46-11) indicated?

YES -

Faulty right side impact sensor (second); replace the right side impact sensor (second) Side Impact Sensor (Second) Replacement, then clear the DTC.

NO -

Go to step 5.

5. Read the DTC.

Is DTC 48-xx (except 48-11) indicated?

YES -

Faulty right side impact sensor (third); replace the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement, then clear the DTC.

NO -

Go to step 6.

6. Read the DTC.

Is DTC 46-11 indicated?

YES -

Go to step 9.

NO -

Go to step 7.

7. Read the DTC.

Is DTC 48-11 indicated?

YES -

Go to step 37.

NO -

Go to step 8.

8. Read the DTC.

Is DTC 43-11 indicated?

YES -

Go to step 65.

NO -

Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, troubleshoot the DTC.

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

10. Check for these connector connections:

- SRS unit connector B (39P) and the SRS unit.
- Floor wire harness 4P connector and the left side impact sensor (first) Side Impact Sensor (First) Replacement.
- Floor wire harness 4P connector and the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
- Floor wire harness 2P connector and the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.

Are the connections OK?

YES -

Go to step 11.

NO -

Repair the poor connections, then clear the DTC, and retest. If DTC 46-11 is still present, go to step 11.

11. Disconnect the negative cable from the battery, then wait at least 3 minutes.

12. Substitute a known-good right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.

13. Reconnect the negative cable to the battery.

14. Clear the DTC memory.

15. Turn the ignition switch to ON (II), then wait for 10 seconds.

16. Read the DTC.

Is DTC 46-11 indicated?

YES -

Go to step 17.

NO -

Faulty right side impact sensor (third); replace the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement, then clear the DTC.

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

18. Disconnect the negative cable from the battery, then wait at least 3 minutes.

19. Return the right side impact sensor (third) which was replaced in step 12.

20. Substitute a known-good right side impact sensor (second) Side Impact Sensor (Second) Replacement.

21. Reconnect the negative cable to the battery.

22. Clear the DTC memory.

23. Turn the ignition switch to ON (II), then wait for 10 seconds.

24. Read the DTC.

Is DTC 46-11 indicated?

YES -

Go to step 25.

NO -

Faulty right side impact sensor (second); replace the right side impact sensor (second) Side Impact Sensor (Second) Replacement, then clear the DTC.

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

26. Disconnect the negative cable from the battery, then wait at least 3 minutes.

27. Disconnect SRS unit connector B (39P) from the SRS unit.

28. Disconnect the floor wire harness 2P connector from the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.

29. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.

30. Measure the resistance between floor wire harness 2P connector (right side impact sensor (third)) terminals No. 1 and No. 2. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 31.

NO -

Short to another wire in the floor wire harness between the right side impact sensor (second) and the right side impact sensor (third); replace the floor wire harness, then clear the DTC.

31. Measure the resistance between body ground and floor wire harness 2P connector (right side impact sensor (third)) terminals No. 1 and No. 2, individually. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 32.

NO -

Short to ground in the floor wire harness between the right side impact sensor (second) and the right side impact sensor (third); replace the floor wire harness, then clear the DTC.

32. Reconnect the negative cable to the battery.

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

34. Measure the voltage between body ground and floor wire harness 2P connector (right side impact sensor (third)) terminals No. 1 and No. 2, individually. There should be less than 0.2 V.

Is the voltage as specified?

YES -

Go to step 35.

NO -

Short to power in the floor wire harness between the right side impact sensor (second) and the right side impact sensor (third); replace the floor wire harness, then clear the DTC.

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

36. Measure the resistance between the floor wire harness 4P connector (right side impact sensor (second)) terminal No. 1 and the floor wire harness 2P connector (right side impact sensor (third)) terminal No. 2, and between the floor wire harness 4P connector (right side impact sensor (second)) terminal No. 4 and the floor wire harness 2P connector (right side impact sensor (third)) terminal No. 1. There should be less than 1.0 Ohms.

Is the resistance as specified?

YES -

Disconnect and reconnect the connector, and then check for the DTC again. If the DTC is still present, replace the SRS unit Service and Repair.

NO -

Open in the floor wire harness between the right side impact sensor (second) and the right side impact sensor (third); replace the floor wire harness, then clear the DTC.

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

38. Check for these connector connections:

- SRS unit connector B (39P) and the SRS unit.
- Floor wire harness 4P connector and the left side impact sensor (first) Side Impact Sensor (First) Replacement.
- Floor wire harness 4P connector and the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
- Floor wire harness 2P connector and the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.

Are the connections OK?

YES -

Go to step 39.

NO -

Repair the poor connections, then clear the DTC, and retest. If DTC 48-11 is still present, go to step 39.

39. Disconnect the negative cable from the battery, then wait at least 3 minutes.

40. Substitute a known-good right side impact sensor (second) Side Impact Sensor (Second) Replacement.

41. Reconnect the negative cable to the battery.

42. Clear the DTC memory.

43. Turn the ignition switch to ON (II), then wait for 10 seconds.

44. Read the DTC.

Is DTC 48-11 indicated?

YES -

Go to step 45.

NO -

Faulty right side impact sensor (second); replace the right side impact sensor (second) Side Impact Sensor (Second) Replacement, then clear the DTC.

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

46. Disconnect the negative cable from the battery, then wait at least 3 minutes.

47. Return the right side impact sensor (second) which was replaced in step 40.

48. Substitute a known-good left side impact sensor (first) Side Impact Sensor (First) Replacement.

49. Reconnect the negative cable to the battery.

50. Clear the DTC memory.

51. Turn the ignition switch to ON (II), then wait for 10 seconds.

52. Read the DTC.

Is DTC 48-11 indicated?

YES -

Go to step 53.

NO -

Faulty left side impact sensor (first); replace the left side impact sensor (first) Side Impact Sensor (First) Replacement, then clear the DTC.

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

54. Disconnect the negative cable from the battery, then wait at least 3 minutes.

55. Disconnect SRS unit connector B (39P) from the SRS unit.

56. Disconnect the floor wire harness 4P connector from the left side impact sensor (first) Side Impact Sensor (First) Replacement.

57. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.

58. Measure the resistance between floor wire harness 4P connector (right side impact sensor (second)) terminals No. 2 and No. 3. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 59.

NO -

Short to another wire in the floor wire harness between the left side impact sensor (first) and the right side impact sensor (second); replace the floor wire harness, then clear the DTC.

59. Measure the resistance between body ground and floor wire harness 4P connector (right side impact sensor (second)) terminals No. 2 and No. 3, individually. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 60.

NO -

Short to ground in the floor wire harness between the left side impact sensor (first) and the right side impact sensor (second); replace the floor wire harness, then clear the DTC.

60. Reconnect the negative cable to the battery.

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

62. Measure the voltage between body ground and floor wire harness 4P connector (right side impact sensor (second)) terminals No. 2 and No. 3, individually. There should be less than 0.2 V.

Is the voltage as specified?

YES -

Go to step 63.

NO -

Short to power in the floor wire harness between the left side impact sensor (first) and the right side impact sensor (second); replace the floor wire harness, then clear the DTC.

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

64. Measure the resistance between the floor wire harness 4P connector (left side impact sensor (first)) terminal No. 1 and the floor wire harness 4P connector (right side impact sensor (second)) terminal No. 3, and between the floor wire harness 4P connector (left side impact sensor (first)) terminal No. 4 and the floor wire harness 4P connector (right side impact sensor (second)) terminal No. 2. There should be less than 1.0 Ohms.

Is the resistance as specified?

YES -

Disconnect and reconnect the connector, and then check for the DTC again. If the DTC is still present, replace the SRS unit Service and Repair.

NO -

Open in the floor wire harness between the left side impact sensor (first) and the right side impact sensor (second); replace the floor wire harness, then clear the DTC.

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

66. Check for these connector connections:

- SRS unit connector B (39P) and the SRS unit.
- Floor wire harness 4P connector and the left side impact sensor (first) Side Impact Sensor (First) Replacement.
- Floor wire harness 4P connector and the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
- Floor wire harness 2P connector and the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.

Are the connections OK?

YES -

Go to step 67.

NO -

Repair the poor connections, then clear the DTC, and retest. If DTC 43-11 is still present, go to step 67.

67. Disconnect the negative cable from the battery, then wait at least 3 minutes.

68. Substitute a known-good left side impact sensor (first) Side Impact Sensor (First) Replacement.

69. Reconnect the negative cable to the battery.

70. Clear the DTC memory.

71. Turn the ignition switch to ON (II), then wait for 10 seconds.

72. Read the DTC.

Is DTC 43-11 indicated?

YES -

Go to step 73.

NO -

Faulty left side impact sensor (first); replace the left side impact sensor (first) Side Impact Sensor (First) Replacement, then clear the DTC.

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

74. Disconnect the negative cable from the battery, then wait at least 3 minutes.

75. Disconnect SRS unit connector B (39P) from the SRS unit.

76. Disconnect the floor wire harness 4P connector from the left side impact sensor (first) Side Impact Sensor (First) Replacement.

77. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.

78. Measure the resistance between floor wire harness 4P connector (left side impact sensor (first)) terminals No. 2 and No. 3. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 79.

NO -

Short to another wire in the floor wire harness between the SRS unit and the left side impact sensor (first); replace the floor wire harness, then clear the DTC.

79. Measure the resistance between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 2 and No. 3, individually. There should be an open circuit or at least 1 MOhms.

Is the resistance as specified?

YES -

Go to step 80.

NO -

Short to ground in the floor wire harness between the SRS unit and the left side impact sensor (first); replace the floor wire harness, then clear the DTC.

80. Reconnect the negative cable to the battery.

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

82. Measure the voltage between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 2 and No. 3, individually. There should be less than 0.2 V.

Is the voltage as specified?

YES -

Go to step 83.

NO -

Short to power in the floor wire harness between the SRS unit and the left side impact sensor (first); replace the floor wire harness, then clear the DTC.

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

84. Measure the resistance between the floor wire harness 4P connector (left side impact sensor (first)) terminal No. 2 and SRS unit connector B (39P) terminal No. 37, and between the floor wire harness 4P connector (left side impact sensor (first)) terminal No. 3 and SRS unit connector B (39P) terminal No. 36. There should be less than 1.0 Ohms.