SIR Diagnostic Trouble Codes
Caution: In order to avoid deploying the air bag when troubleshooting the SIR
system, use only the equipment specified in this manual and the instructions
given in this manual. Failure to use the specified equipment as instructed
could cause air bag deployment, personal injury to you or someone else,
or unnecessary SIR system repairs.
The SIR Diagnostic System Check must always
be the starting point of any SIR system diagnosis. The SIR Diagnostic System
Check checks for proper AIR BAG warning lamp operation and checks for SIR
Diagnostic Trouble Codes (DTC) using the scan tool. The following describes
the difference between current and history SIR DTCs:
| • | Current SIR DTCs - Malfunctions that are presently being
detected. Random Access Memory (RAM) stores the current SIR DTCs. Turning
the ignition switch to the OFF position erases current SIR DTCs. The presence
of a current SIR DTC will cause the inflatable restraint Sensing and Diagnostic
Module (SDM) to turn ON the AIR BAG warning lamp. |
| • | History SIR DTCs - All malfunctions detected since last
clearing of history memory. Electrically Erasable Programmable Read Only Memory
(EEPROM) stores the history SIR DTCs. A scan tool clear codes command will
erase history SIR DTCs. |
Some SIR DTCs are latched and can not be cleared. Latched SIR DTCs
will require replacement of the SDM after proper diagnostics.
Use of Special Tools
You should be familiar with the tools in this service category listed
under the heading Special Tools. You should know how to measure voltage and
resistance. Diagnosis requires proper use of the following tools:
| • | The J 38715-A
SIR
Driver/Passenger Load Tool |
| • | The J 35616
Connector
Test Adapter Kit |
