Diagnostic System Check - SIR

Diagnostic System Check - SIR

Notice: Never us an SDM that is damaged or has been subjected to water intrusion. The use of an SDM that is damaged or has been subjected to water intrusion can result in a malfunctioning SIR system and cause vehicle damage.

The Diagnostic System Check - SIR must always be the starting point for any supplemental inflatable restraint (SIR) diagnosis. The Diagnostic System Check - SIR 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.

1. Perform the Diagnostic System Check - SIR, which reveals DTCs through the use of the scan tool. It also inspects for proper airbag indicator operation.
2. Refer to the proper diagnostic chart as directed by the Diagnostic System Check - SIR. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
3. Repeat the Diagnostic System Check - SIR 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 airbag fuse to the sensing and diagnostic module (SDM). The SDM responds by flashing the airbag 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.