Important: If the vehicle interior has been exposed to extensive water intrusion such as water leaks, driving through high water, flooding, or other causes, the sensing and diagnostic module (SDM) and SDM connector may need to be replaced.
With the ignition OFF, inspect the area around the SDM, including the carpet. If any significant soaking or evidence of previous soaking is detected, the water must be removed, water damage repaired, and the SDM and SDM connector must be replaced. Before attempting any of these repairs, the supplemental inflatable restraints (SIR) must be disabled. Refer to Disabling the SIR System and Inflatable Restraint Sensing and Diagnostic Module Replacement for instructions on how to disable the SIR and replace the SDM.
The SIR Diagnostic System Check must always be the starting point for any SIR diagnosis. The Diagnostic System Check reveals DTCs through the use of the scan tool. The diagnostic procedures used in this section are designed to find any repair SIR conditions. To get the best results, it is important to use the diagnostic charts and follow the sequence listed below.
- Perform the SIR Diagnostic System Check, which reveals DTCs through the use of the scan tool. It also checks for proper air bag indicator operation.
- Refer to the proper diagnostic chart as directed by the SIR Diagnostic System Check. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
- Repeat the SIR Diagnostic System Check after any repair or diagnostic procedures have been performed to ensure that the repair has been made correctly and that no other malfunction exists.
Circuit Description
When the ignition switch is first turned ON, ignition voltage is supplied from the air bag fuse to find the SDM at input terminal 26. The SDM responds by flashing the air bag indicator 7 times and then turning it OFF while the SDM performs tests on the SIR.
Diagnostic Aids
The order in which DTCs are diagnosed is very important. Failure to diagnose the DTCs in the order specified may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
Step | Action | Yes | No |
|---|---|---|---|
|
Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section. Caution: Refer to SRS Sensing and Diagnostic Module Handling Caution in the Preface section. | |||
1 |
Does the indicator flash 7 times? | System OK | Go to Step 2 |
2 |
Are any DTCs displayed on the scan tool? | Go to Step 3 | |
3 | Inspect the fuse F8 in the interior fuse box. Is fuse F8 open? | Go to Step 4 | Go to Step 5 |
4 | Replace fuse F8. Is the repair complete? | System OK | -- |
5 |
Is the wiring shorted? | Go to Step 12 | Go to Step 6 |
6 |
Is the wiring shorted? | Go to Step 12 | Go to Step 7 |
7 | Inspect the wiring open between terminal 28 of the SDM and the ground G204. Is the wiring opened? | Go to Step 12 | Go to Step 8 |
8 |
Is the voltage between 11-14 volts? | Go to Step 10 | Go to Step 9 |
9 | Repair the wiring of the cigar lighter socket. Is the repair complete? | System OK | -- |
10 | Inspect the wiring shortage or loop open between terminal 7 of the connector C213 and terminal 13 of the DLC. Is the wiring opened or shorted? | Go to Step 12 | Go to Step 11 |
11 | Inspect the wiring shortage or loop open between terminal 7 of the connector C213 and terminal 54 of the SDM wiring connector. Is the wiring open or shorted? | Go to Step 12 | Go to Step 13 |
12 | Repair the wiring. Is the repair complete? | System OK | -- |
13 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the replacement complete? | System OK | -- |
