Diagnostic Trouble Codes
CAUTION: In order to avoid deploying the air bag when troubleshooting the SRS
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 SRS system repairs.
The SRS Diagnostic System Check must always be the starting
point of any SRS diagnosis. The SRS Diagnostic System Check inspects for
proper AIR BAG warning lamp operation and inspects for SRS diagnostic
trouble codes (DTC) using the scan tool. The following describes the
difference between current and history DTCs:
| • | Current DTCs include malfunctions that are presently being detected.
Random access memory (RAM) stores the current DTCs. Turning the ignition
switch to the OFF position erases current DTCs. The presence of a current
DTC will cause the supplemental restraint sensing and the diagnostic
module (SDM) to turn the AIR BAG warning lamp to the ON position. |
| • | History DTCs includes all malfunctions detected since the last
clearing of the history memory. Electrically erasable programmable read only
memory (EEPROM) stores the history DTCs. A scan tool clear codes command
erases history DTCs. |
Some DTCs are latched and may not be cleared. Latched 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
SRS Driver/Passenger Load Tool |
| • | The J 35616
Connector Test Adapter Kit |
