DTC B0057, B0058, or B0059. Buick LaCrosse 2005

For 1990-2009 cars only

Makes 🢒 Buick 🢒 2005 🢒 LaCrosse 🢒 Restraints 🢒 SIR 🢒 DTC B0057, B0058, or B0059

Circuit Description

The passenger seat belt pretensioner deployment loop consists of the following components:

•	An inflatable restraint seat belt pretensioner - RF

•	The seat belt pretensioner - RF high circuits

•	The seat belt pretensioner - RF low circuits

A shorting bar used within the seat belt pretensioner connector which will short together both seat belt pretensioner high and low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the pretensioner during servicing. During a frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the seat belt pretensioner. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a diagnostic trouble code (DTC) will be stored in memory.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

•	DTC B0057 Right Front Pretensioner Deployment Loop Resistance Low

•	DTC B0058 Right Front Pretensioner Deployment Loop Open

•	DTC B0059 Right Front Pretensioner Deployment Loop Voltage Out of Range

Conditions for Running the DTC

Ignition voltage is within the normal operating voltage range.

Conditions for Setting the DTC

•	DTC B0057 will set when the seat belt pretensioner - RF deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

•	DTC B0058 will set when one of the following conditions occurs:

-	The seat belt pretensioner - RF high circuit is less than 2.4 volts and the seat belt pretensioner - RF deployment loop is more than 6 ohms for 500 milliseconds.

-	The seat belt pretensioner - RF deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

•	DTC B0059 when one of the following conditions occur:

-	The seat belt pretensioner - RF high and/or low circuits is short to ground or short to voltage for 500 milliseconds.

-	The seat belt pretensioner - RF high circuit is less than 2.4 volts and seat belt pretensioner - RF deployment loop resistance is less than 6 ohms for 500 milliseconds.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON via Class 2 serial data.

Conditions for Clearing the DTC

•	The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

•	A history DTC will clear once 255 malfunction free ignition cycles have occurred.

Diagnostic Aids

The following are possible causes of the malfunction:

•	A short between the seat belt pretensioner - RF high and low circuits.

•	An open or a high resistance in the seat belt pretensioner - RF high or low circuits.

•	A short to ground or a short to voltage in the seat belt pretensioner - RF high or low circuits.

•	The seat belt pretensioner - RF connector

•	The SDM connector

•	A malfunctioning seat belt pretensioner

•	A malfunctioning SDM

Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

Tests to see if the malfunction is caused by the seat belt pretensioner - RF.

Tests to see what DTCs are present. If DTC B0057 is present, test the seat belt pretensioner - RF for a short between high and low circuits. If DTC B0058 is present, test the seat belt pretensioner - RF high and low circuits for an open and for high resistance. If DTC B0059 is present, test the seat belt pretensioner - RF high and low circuits for a short to ground and for a short to voltage.

Step	Action	Yes	No
Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2	Turn OFF the ignition. Disconnect seat belt pretensioner - RF wiring harness in-line connector. Refer to Seat Belt Buckle Pretensioner Replacement . Inspect the component and harness sides of the in-line connector for the seat belt pretensioner for damage or corrosion that may cause the malfunction. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Does the connector exhibit any signs of damage or corrosion?	Go to Step 3	Go to Step 4
3	If the in-line connector for the seat belt pretensioner - RF wiring harness is damaged, the seat belt pretensioner - RF wiring harness must be replaced. If the wiring harness side of the seat belt pretensioner connector is damaged, replace the harness side of the connector. Refer to Connector Repairs in Wiring Systems. Did you complete the repair?	Go to Step 11	--
4	Connect the J 38715-A SIR Driver/Passenger Load Tool to the harness side of the seat belt pretensioner - RF connector. Use PASSENGER INFLATOR connector. Turn ON the ignition, with the engine OFF. With the scan tool, request the SIR DTC display. Does the scan tool indicate that DTC B0057, B0058, or B0059 are current?	Go to Step 6	Go to Step 5
5	Turn OFF the ignition. Disconnect and remove the J 38715-A . Connect seat belt pretensioner - RF wiring harness in-line connector. Remove the seat belt pretensioner - RF connector. Refer to Seat Belt Buckle Pretensioner Replacement Connect the J 38715-A SIR Driver/Passenger Load Tool to the seat belt pretensioner - RF connector. Use the PASSENGER INFLATOR connector. Turn ON the ignition, with engine OFF. With the scan tool, request the SIR DTC display. Does the scan tool indicate that DTC B0057, B0058, or B0059 are current?	Go to Step 9	Go to Step 8
6	Turn OFF the ignition. Disconnect and remove the J 38715-A . Disconnect the inflatable restraint sensing and diagnostic module (SDM) connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Inspect the SDM connector for damage or corrosion that may cause a malfunction in the seat belt pretensioner - RF high and/or low circuits. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 11	Go to Step 7
7	If DTC B0057 is present, test the seat belt pretensioner - RF for a short between the high and low circuits. If DTC B0058 is present, test the seat belt pretensioner - RF high and low circuits for an open and for high resistance. If DTC B0059 is present, test the seat belt pretensioner - RF high and low circuits for a short to ground and for a short to voltage. All the above conditions refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 11	Go to Step 10
8	Turn OFF the ignition. Replace the seat belt pretensioner - RF. Refer to Seat Belt Buckle Pretensioner Replacement . Did you complete the replacement?	Go to Step 11	--
9	Turn OFF the ignition. Replace the Seat Belt Buckle Pretensioner - RF Wiring Harness connector. Refer to Connector Repairs in Wiring Systems. Did you complete the replacement?	Go to Step 11	--
10	Turn OFF the ignition. Replace the SDM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement?	Go to Step 11	--
11	Connect all SIR components. Turn ON the ignition, with the engine OFF. Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset?	Go to Step 2	System OK