43-1x
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)
- 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 Procedures.
- 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 SRS Unit Update, 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 48-1x (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 4.
4. Clear the DTC memory.
5. Turn the ignition switch to ON (II), then wait for 10 seconds.
6. Read the DTC.
Is DTC 46-1x (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 7.
7. Clear the DTC memory.
8. Turn the ignition switch to ON (II), then wait for 10 seconds.
9. Read the DTC.
Is DTC 43-1x (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 10.
10. Clear the DTC memory.
11. Turn the ignition switch to ON (II), then wait for 10 seconds.
12. Read the DTC.
Is DTC 43-11 indicated?
YES -
Go to step 16.
NO -
Go to step 13.
13. Clear the DTC memory.
14. Turn the ignition switch to ON (II), then wait for 10 seconds.
15. Read the DTC.
Is DTC 46-11 indicated?
YES -
Go to step 63.
NO -
Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, troubleshoot the DTC.�
16. Turn the ignition switch to LOCK (0).
17. Check the connections between SRS unit connector B (39P) and the SRS unit, and between the floor wire harness 4P connector and the left side impact sensor (first) Side Impact Sensor (First) Replacement.
Are the connections OK?
YES -
Go to step 18.
NO -
Replace the floor wire harness, then clear the DTC.�
18. Disconnect the negative cable from the battery, then wait at least 3 minutes.
19. Disconnect the floor wire harness 4P connector from the left side impact sensor (first).
20. Substitute a known-good left side impact sensor (first) and recheck.
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 43-11 indicated?
YES -
Go to step 25.
NO -
Faulty left side impact sensor (first); replace the left side impact sensor (first) Side Impact Sensor (First) Replacement , then clear the DTC.�
25. Disconnect the negative cable from the battery, then wait at least 3 minutes.
26. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
27. Substitute a known-good right side impact sensor (second) and recheck.
28. Reconnect the negative cable to the battery.
29. Clear the DTC memory.
30. Turn the ignition switch to ON (II), then wait for 10 seconds.
31. Read the DTC.
Is DTC 43-11 indicated?
YES -
Go to step 32.
NO -
Faulty right side impact sensor (second); replace the right side impact sensor (second) Side Impact Sensor (Second) Replacement, then clear the DTC.�
32. Disconnect the negative cable from the battery, then wait at least 3 minutes.
33. Disconnect the floor wire harness 2P connector from the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.
34. Substitute a known-good right side impact sensor(third) and recheck.
35. Reconnect the negative cable to the battery.
36. Clear the DTC memory.
37. Turn the ignition switch to ON (II), then wait for 10 seconds.
38. Read the DTC.
Is DTC 43-11 indicated?
YES -
Go to step 39.
NO -
Faulty right side impact sensor (third); replace the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement, then clear the DTC.�
39. Turn the ignition switch to LOCK (0).
40. Disconnect the negative cable from the battery, then wait at least 3 minutes.
41. Disconnect SRS unit connector B (39P) from the SRS unit.
42. Disconnect the floor wire harness 4P connector from the left side impact sensor (first) Side Impact Sensor (First) Replacement.
43. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
44. Measure the resistance between floor wire harness 4P connector (left side impact sensor (first)) 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 45.
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.�
45. Measure the resistance between floor wire harness 4P connector (left side impact sensor (first)) terminals No. 3 and No. 4. There should be an open circuit or at least 1 MOhms.
Is the resistance as specified?
YES -
Go to step 46.
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.�
46. Measure the resistance between body ground and floor wire harness 4P connector (left side impact sensor (first)) 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 47.
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.�
47. Measure the resistance between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 3 and No. 4, individually. There should be an open circuit or at least 1 MOhms.
Is the resistance as specified?
YES -
Go to step 48.
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.�
48. Disconnect the floor wire harness 2P connector from the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.
49. Measure the resistance between body ground and floor wire harness 4P connector (right side impact sensor (second)) terminals No. 3 and No. 4, individually. There should be an open circuit or at least 1 MOhms.
Is the resistance as specified?
YES -
Go to step 50.
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.�
50. Reconnect the negative cable to the battery.
51. Turn the ignition switch to ON (II).
52. Measure the voltage between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 1 and No. 2, individually. There should be less than 0.2 V.
Is the voltage as specified?
YES -
Go to step 53.
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.�
53. Measure the voltage between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 3 and No. 4, individually. There should be less than 0.2 V.
Is the voltage as specified?
YES -
Go to step 54.
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.�
54. Measure the voltage between body ground and floor wire harness 4P connector (right side impact sensor (second)) terminals No. 3 and No. 4, individually. There should be less than 0.2 V.
Is the voltage as specified?
YES -
Go to step 55.
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.�
55. Turn the ignition switch to LOCK (0).
56. Disconnect the negative cable from the battery, then wait at least 3 minutes.
57. Install a jumper wire between SRS unit connector B (39P) terminal No. 36 and No. 37.
58. Measure the resistance between floor wire harness 4P connector (left side impact sensor (first)) terminals No. 1 and No. 2. There should be less than 1.0 Ohms.
Is the resistance as specified?
YES -
Go to step 59.
NO -
Open 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.�
59. Install a jumper wire between floor wire harness 4P connector (left side impact sensor (first)) terminals No. 1 and No. 2.
60. Measure the resistance between floor wire harness 4P connector (right side impact sensor (second)) terminals No. 1 and No. 2. There should be less than 1.0 Ohms.
Is the resistance as specified?
YES -
Go to step 61.
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.�
61. Install a jumper wire between floor wire harness 4P connector (right side impact sensor (second)) terminals No. 3 and No. 4.
62. Measure the resistance between floor wire harness 2P connector (right side impact sensor (third)) terminals No. 1 and No. 2. There should be less than 1.0 Ohms.
Is the resistance as specified?
YES -
Faulty SRS unit; replace the SRS unit SRS Unit Replacement.�
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.�
63. Check the connections between SRS unit connector B (39P) and the SRS unit, and between the floor wire harness 4P connector and the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
Are the connections OK?
YES -
Go to step 64.
NO -
Replace the floor wire harness, then clear the DTC.�
64. Disconnect the negative cable from the battery, then wait at least 3 minutes.
65. Disconnect the floor wire harness 4P connector from the left side impact sensor (first) Side Impact Sensor (First) Replacement.
66. Substitute a known-good left side impact sensor (first) and recheck.
67. Reconnect the negative cable to the battery.
68. Clear the DTC memory.
69. Turn the ignition switch to ON (II), then wait for 10 seconds.
70. Read the DTC.
Is DTC 43-11 or 46-11 indicated?
YES -
Go to step 71.
NO -
Faulty left side impact sensor (first); replace the left side impact sensor (first) Side Impact Sensor (First) Replacement, then clear the DTC.�
71. Disconnect the negative cable from the battery, then wait at least 3 minutes.
72. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
73. Substitute a known-good right side impact sensor(second) and recheck.
74. Reconnect the negative cable to the battery.
75. Clear the DTC memory.
76. Turn the ignition switch to ON (II), then wait for 10 seconds.
77. Read the DTC.
Is DTC 43-11 or 46-11 indicated?
YES -
Go to step 78.
NO -
Faulty right side impact sensor (second); replace the right side impact sensor (second) Side Impact Sensor (Second) Replacement, then clear the DTC.�
78. Disconnect the negative cable from the battery, then wait at least 3 minutes.
79. Disconnect SRS unit connector B (39P) from the SRS unit.
80. Disconnect the floor wire harness 4P connector from the right side impact sensor (second) Side Impact Sensor (Second) Replacement.
81. Disconnect the floor wire harness 2P connector from the right side impact sensor (third) Right Side Impact Sensor (Third) Replacement.
82. Measure the resistance between floor wire harness 4P connector (right side impact sensor (second)) terminals No. 3 and No. 4. There should be an open circuit or at least 1 MOhms.
Is the resistance as specified?
YES -
Go to step 83.
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.�
83. Disconnect the floor wire harness 4P connector from the left side impact sensor (first) Side Impact Sensor (First) Replacement.
84. Reconnect the negative cable to the battery.
85. Turn the ignition switch to ON (II).
86. Measure the voltage between body ground and floor wire harness 4P connector (left side impact sensor (first)) terminals No. 3 and No. 4. There should be less than 0.2 V.
Is the voltage as specified?
YES -
Go to step 87.
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.�
87. Turn the ignition switch to LOCK (0).
88. Install a jumper wire between floor wire harness 4P connector (left side impact sensor (first)) terminals No. 3 and No. 4.
89. Measure the resistance between floor wire harness 4P connector (right side impact sensor (second)) terminals No. 1 and No. 2. There should be less than 1.0 Ohms.
Is the resistance as specified?
YES -
Faulty SRS unit; replace the SRS unit SRS Unit Replacement.�
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.�