| Table 1: | DTC B1171 Internal SDM Failure |
Circuit Description
DTC B1171 is an indication of a potential internal inflatable restraint sensing and diagnostic module (SDM) malfunction. DTC B1171 will set upon detection of any condition in the table below.
Conditions for Setting the DTC
Malfunction | Detection Test |
|---|---|
Air Bag 23 VLR voltage out of normal operating range. | Power-ON, Power-OFF, Continuous Monitoring |
Crash data recording reserve voltage discharge time failure for three consecutive ignition cycles. | Power-OFF |
The calculated checksum for internal memory does not match the stored value. | Power-On |
The accelerometer is malfunctioning. | Power-On, Continuous monitoring |
A current source or a current sink is malfunctioning. | Power-ON |
The temporary memory storage area is malfunctioning. | Power-On |
The Inflatable Restraint Sensing and Diagnostic Module (SDM) is unable to read from or write to EEPROM. | Power-On |
The inflator arming sensor inside the Inflatable Restraint Sensing and Diagnostic Module (SDM) is not closed during a deployment event. | Asynchronously |
DTC B1125 is set | Continuous monitoring |
One of the FET drivers is malfunctioning | Power-ON |
The permanent memory storage area is malfunctioning. | Power-On |
Action Taken When the DTC Sets
| • | The SDM sets a diagnostic trouble code. |
| • | The SDM commands the instrument cluster in order to turn ON the AIR BAG warning lamp. |
Conditions for Clearing the MIL/DTC
The DTC will clear when one of the following conditions is met:
| • | Current DTC |
| You do not detect the malfunction for 500 milliseconds and DTC B1125 has never been set. |
| • | History DTC |
| - | You issue a scan tool CLEAR CODES command. |
| - | 250 malfunction free ignition cycles have occurred. |
Diagnostic Aids
DTC B1171 indicates a fault within the SDM. Replace the SDM if DTC B1171 sets, current or history.
Notice: When DTC B1125 has been set it is necessary to replace the inflatable restraint Sensing and Diagnostic Module (SDM). Setting DTC B1125 will also cause DTC B1171 to set. When a scan tool clear codes command is issued and the malfunction is no longer present, DTC B1171 will remain current. Make sure that the short to voltage condition is repaired prior to installing a replacement SDM to avoid damaging the SDM.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
2 | Is DTC B1125 set? | -- | ||
3 |
Are the repairs complete? | -- | -- |
