To use the scan tool, turn the ignition OFF, connect the scan tool to the data link connector (DLC), and turn the ignition ON.
Follow the instructions in the scan tool manual. The SDM sends serial data from pin 2 of the SDM to pin 1 of the DLC via other controllers.
Checking the diagnostic system of the inflatable restraint system (SIR)
Note: If a large amount of water has entered the vehicle interior, such as due to leaks, driving through deep water, flooding, or other causes, the Sensor and Diagnostic Module (SDM) and the SDM connector may need to be replaced. After setting the ignition to the OFF position, inspect the area around the SDM module, including the mat. If there is significant wetness or signs of past wetness, remove the water, repair water-related damage, and replace the SDM module and SDM connector. Before attempting to correct any of these problems, the Airbag Inflator system (SIR) must be deactivated. For instructions on disabling the SIR system and replacing the SDM module, see the chapters "Disabling the Airbag System (SIR)" and "Sensor and Diagnostic Module (SDM)" in this section.
Any troubleshooting of the airbag Inflator system (SIR) must begin by checking the SIR diagnostic system. Checking the diagnostic system with a diagnostic device allows you to read diagnostic trouble codes (DTCs). This section describes procedures for detecting SIR conditions that require repair. To get the best results, it is important to use diagnostic cards and follow the following steps.
1. Perform the Supplemental Inflatable Restraint (SIR) Diagnostic System Check, which allows you to retrieve diagnostic trouble codes (DTCs) using a scan tool. At the same time, the air bag warning lamp is checked for proper operation.
2. Refer to the relevant diagnostic card according to the procedure for checking the diagnostic system of the Inflatable Airbag system (SIR). Skipping these procedures can lead to increased diagnostic time, incorrect fault identification, and erroneous replacement of spare parts.
3. Please check the Airbag Diagnostic System (SIR) again after any repairs or diagnostics to make sure that the repairs are correct and that there are no other problems.
Description of the chain
The sensing and diagnostic module (SDM) receives voltage from the battery, which serves as the primary power source, via SDM terminal 31. Additionally, during ignition, voltage supplied from the instrument panel fuse block to SDM terminal 32 serves as a backup power source. In response, the SDM flashes the air bag indicator lamp seven times and then turns it off while it performs SIR system tests.
Diagnostic recommendations
The order in which you research diagnostic trouble codes is very important. Failure to follow the specified order in which you review diagnostic trouble codes may result in increased diagnostic time, incorrect fault determination, and incorrect replacement of spare parts.
Checking the diagnostic system of the inflatable restraint system (SIR)
Caution! The sensing and diagnostic module (SDM) can retain sufficient voltage to deploy the air bags and pretensioners for 1 minute after the ignition is turned off and the fuse is removed. If the air bags and pretensioners are not disconnected, do not begin servicing until one minute has passed after disconnecting power from the SDM. Failure to do so could result in personal injury.
Attention! Handle the Sensor and Diagnostic module (SDM) very carefully during maintenance. Do not hit or shake the SDM. Never connect power to the Airbag Inflator system (SIR) unless the SDM is rigidly connected to the vehicle. In order for the Airbag Inflator system (SIR) to work correctly, all the mounting bolts of the SDM sensor and diagnostic module must be carefully tightened, and the arrow on the SDM must point towards the front of the vehicle. If the SDM module is not firmly attached to the vehicle, the included module may trigger, causing the airbags to release unexpectedly and causing injury.
| Step | Operation | Values | Yes | No |
| 1 |
|
-
|
The system is normal
|
Go to Step 2
|
| 2 |
|
-
|
Go to
Diagnostic Trouble Code (DTC) Check Procedure
|
Go to Step 3
|
| 3 |
Check fuse EF2 in the engine fuse box.
Is the EF2 fuse blown?
|
-
|
Replace fuse EF2
|
Go to Step 4
|
| 4 |
Check fuse F5 in the instrument panel fuse box.
Is fuse F5 blown?
|
-
|
Replace fuse F5.
|
Go to Step 5
|
| 5 |
Is there a break or short in the wiring? If so, correct the wiring.
|
-
|
-
|
Go to Step 6
|
| 6 |
Is there a break or short in the wiring? If so, replace the airbag wiring.
|
-
|
-
|
Go to Step 7
|
| 7 |
|
-
|
-
|
Go to Step 8
|
| 8 |
Is the proper voltage being supplied to the diagnostic tool?
|
9 - 16 V
|
Go to Step 10
|
Go to Step 9
|
| 9 |
Correct the power supply of the diagnostic tool.
|
-
|
-
|
-
|
| 10 |
Check the wiring for an open or short between terminal 8 of the SDM connector and terminal 1 of the data link connector (DLC).
Is there a break or short in the wiring? If so, correct the wiring.
|
-
|
-
|
Replace the SDM module.
|