To use the scan tool, turn the ignition to OFF, connect the scan tool to the data line connector (DLC) and turn the ignition to the ON position.
Follow the instructions in the manual for the diagnostic tool. The SDM sends serial data from SDM pin 2 to DLC pin 1 with other controllers.
Checking the diagnostic system of the airbag system (SIR)
Note: If a large amount of water enters the vehicle interior, such as from leaks, driving through deep water, flooding, or other causes, the sensing and diagnostic module may need to be replaced (SDM) and SDM connector. With the ignition in the OFF position, inspect the area around the SDM, including the mat. If there is significant soaking or signs of soaking in the past, remove the water, repair water damage, and replace the SDM and SDM connector. The airbag system must be disabled before any of these problems can be repaired (SIR). For instructions on disabling the SIR system and replacing the SDM, see chapters "Deactivating the airbag system (SIR) " And "Sensor and diagnostic module (SDM) " in this section.
Any troubleshooting of the airbag system (SIR) you must start by checking the SIR diagnostic system. Checking the diagnostic system with a scan tool allows you to read diagnostic trouble codes (DTC). This section describes procedures for identifying SIR conditions that require repair. For best results, it is important to use the diagnostic charts and follow the steps below.
1. Perform the Airbag System Diagnostic System Check (SIR), which allows the scan tool to obtain diagnostic trouble codes (DTC). At the same time, the correct operation of the airbag warning lamp is checked.
2. Refer to the appropriate diagnostic card according to the procedure for checking the diagnostic system of the airbag system (SIR). Omitting these procedures can result in increased diagnostic time, incorrect fault identification, and erroneous replacement of spare parts.
3. Repeat the Airbag Diagnostic System Check (SIR) after any repair or diagnosis, to make sure that the repair is correct and there are no other problems.
Circuit Description
Sensor and diagnostic module (SDM) receives voltage from the battery, which serves as the main power source, through terminal 31 of the SDM. Additionally, during ignition, the voltage supplied from the instrument panel fuse box to terminal 32 of the SDM is used as a backup power source. The SDM responds by flashing the airbag warning light seven times and then turning it off while it performs SIR system checks.
Diagnostic Recommendations
The order in which diagnostic trouble codes are examined is very important. Failure to follow the order in which DTCs are dealt with can result in increased diagnostic time, incorrect fault identification, and erroneous replacement of parts.
Checking the diagnostic system of the airbag system (SIR)
Attention! Sensor and diagnostic module (SDM) can maintain sufficient voltage to deploy the airbags and pretensioners for 1 minute after the ignition is turned off and the fuse has been removed. If the airbags and pretensioners are not disconnected, do not start service until one minute has passed after disconnecting power from the SDM. Failure to do so may result in injury.
Attention! During maintenance, handle the sensing and diagnostics module (SDM) very careful. Do not hit or shake the SDM. Never connect power to the airbag system (SIR), if the SDM is not hardwired to the vehicle. To make the airbag system (SIR) is working correctly, all SDM sensor and diagnostic module mounting bolts must be properly tightened, and the arrow on the SDM must point towards the front of the vehicle. If the SDM is not securely attached to the vehicle, the enabled module may deploy, causing the airbags to deploy unexpectedly and may result in injury.
Step | Operation | Values | Yes | No |
1 |
|
-
|
System OK
|
Go to Step 2
|
2 |
|
-
|
Go to
Diagnostic Trouble Code Check Procedure (DTC)
|
Go to Step 3
|
3 |
Check fuse EF2 in the engine fuse box.
Is fuse EF2 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 yes, correct the wiring.
|
-
|
-
|
Go to Step 6
|
6 |
Is there a break or short in the wiring? If there is, replace the airbag wiring.
|
-
|
-
|
Go to Step 7
|
7 |
|
-
|
-
|
Go to Step 8
|
8 |
Is the correct 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 wiring for open or short between SDM connector pin 8 and diagnostic connector pin 1 (DLC).
Is there a break or short in the wiring? If yes, correct the wiring.
|
-
|
-
|
Replace SDM.
|