DTC B1171 Internal SDM Failure. Cadillac Eldorado 1999

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Restraints 🢒 SIR 🢒 DTC B1171 Internal SDM Failure

Table 1:

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 panel cluster (IPC) in order to turn ON the AIR BAG warning lamp.

Conditions for Clearing the MIL/DTC

•	Current DTC

The malfunction has not been detected for 500 milliseconds.

•	History DTC

-	You issue a scan tool CLEAR CODES command.

-	250 malfunction free ignition cycles occur.

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.

DTC B1171 Internal SDM Failure

Step	Action	Value(s)	Yes	No
1	Was the SIR Diagnostic System Check performed?	--	Go to Step 2	Go to SIR Diagnostic System Check
2	Is DTC B1125 set?	--	Go to DTC B1125 Driver/Pass Deploy Loop Short to Voltage	Go to Step 3
3	Turn the ignition switch to the OFF position. Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Have the repairs been completed?	--	Go to SIR Diagnostic System Check	--

Step

Action

Value(s)

Yes

Was the SIR Diagnostic System Check performed?

Go to Step 2

Go to SIR Diagnostic System Check

Is DTC B1125 set?

Go to DTC B1125 Driver/Pass Deploy Loop Short to Voltage

Go to Step 3

Turn the ignition switch to the OFF position.
Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Have the repairs been completed?

Go to SIR Diagnostic System Check