Buick Regal: DTC B0019 or B0020
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
- Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
DTC Descriptors
DTC B0019
Passenger Instrument Panel Air Bag Deployment Loop Stage 1
DTC B0020
Passenger Instrument Panel Air Bag Deployment Loop Stage 2
For symptom byte information refer to Symptom Byte List.
Diagnostic Fault Information
Circuit/System Description
During a side or 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 an air
bag or pretensioner. There are 2
shorting bars which will short the control circuits together when the connector
is disconnected. This will help to
prevent unwanted deployment of the air bag or pretensioner during servicing.
Conditions for Running the DTC
Ignition voltage is between 9 - 16 V.
Conditions for Setting the DTC
B0019 01, B0020 01
The air bag control circuit is shorted to voltage for 2 s.
B0019 02, B0020 02
The air bag control circuit is shorted to ground for 2 s.
B0019 04, B0020 04
The air bag control circuit is open for 2 s.
B0019 0D, B0020 0D
The air bag deployment loop resistance is greater than 4.2 Ω for 2 s.
B0019 0E, B0020 0E
The air bag deployment loop resistance is less than 1.4 Ω for 2 s.
Action Taken When the DTC Sets
- The inflatable restraint sensing and diagnostic module requests the
instrument cluster to illuminate the
AIR BAG indicator.
- The inflatable restraint sensing and diagnostic module will store a DTC,
however if an event occurs the
system will still attempt deployments.
Conditions for Clearing the DTC
- The condition for setting the DTC no longer exists.
- A history DTC will clear once 100 malfunction-free ignition cycles have
occurred.
Diagnostic Aid
NOTE: The following diagnostic aids apply for both current and history
DTCs.
An incorrectly installed connector position assurance (CPA) or incorrectly
seated connector can cause a shorting
bar to short both control circuits together. Check the connectors and CPAs if a
DTC with symptom byte 02 or 0E
is set, to ensure the shorting bars are not causing the circuits to be shorted
together. Shorting bars are used in the
locations listed below:
- Passenger instrument panel air bag
- Inline harness connectors
- Harness side of the inflatable restraint sensing and diagnostic module
connector
Terminal fretting or incorrectly seated connectors can cause an open/high
resistance condition. Check the circuit
terminals for fretting or incorrectly seated connector if a DTC with symptom
byte 04 or 0D is set.
Reference Information
Schematic Reference
SIR Wiring Schematics
Connector End View Reference
Component Connector End View Index
Description and Operation
Supplemental Inflatable Restraint System Description and Operation
Electrical Information Reference
- Circuit Testing
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs
- Connector Repairs
Scan Tool Reference
Refer to Control Module References for scan tool information
Special Tools
EL-38125-580 Terminal Release Tool Kit
Circuit/System Verification
NOTE:
- Refer to SIR Service Precautions.
- Inspect all terminals for damage or corrosion when disconnecting
connectors. Damage or corrosion in the following requires repair or
replacement of the affected component/connector.
- Passenger instrument panel air bag
- inflatable restraint sensing and diagnostic module
- Passenger instrument panel air bag wiring harness connector
- inflatable restraint sensing and diagnostic module wiring
harness
connector
- The connector and connector position assurance (CPA) may seat
independent of each other. Both the connector and CPA should seat with
an audible and/or tactile click. The CPA isolates the shorting-bars within
the connector allowing the deployment circuit to operate properly.
- If the condition is intermittent or cannot be duplicated,
disconnect the
connectors and add dielectric grease / lubricant (Nyogel 760G or
equivalent, meeting GM specification 9986087). This procedure will correct
the high resistance condition due to terminal fretting corrosion.
1. Verify the scan tool Deployment Loop Resistance parameters stay
consistently between 2.1 - 4.0 Ω
without any spikes or dropouts while moving the harness near each connector
listed below:
- F101 Passenger Instrument Panel Air Bag
- Inline harness connector X207
- K36 Inflatable Restraint Sensing and Diagnostic Module
- If less than 2.1 Ω or greater than 4.0 Ω
Refer to Circuit/System Testing.
- If there are spikes or dropouts, perform the following:
- Inspect each connector terminal and harness for damage or corrosion and
repair as necessary
- Apply dielectric grease / lubricant (Nyogel 760G or equivalent, meeting
GM specification 9986087)
to each connector terminal
- Insure each connector and CPA is correctly seated.
- Go to next step: If between 2.1 - 4.0 Ω without any spikes or
dropouts
2. All OK.
Circuit/System Testing
1. Ignition OFF, scan tool disconnected, disconnect the X207 inline harness
connector for the F101
Passenger Instrument Panel Air Bag. It may take up to 2 min for all vehicle
systems to power down.
2. Test for greater than 25 Ω between the appropriate control circuit terminals
listed below on the K36
Inflatable Restraint Sensing and Diagnostic Module side of the connector:
- F101 Passenger Instrument Panel Air Bag stage 1 X207 terminal 1 and 2
- F101 Passenger Instrument Panel Air Bag stage 2 X207 terminal 3 and 4
- If 25 Ω or less
- Disconnect the X1 harness connector at the K36 inflatable restraint
sensing and diagnostic module.
NOTE: Some connectors may be equipped with shorting bars as a
safety
component to prevent accidental deployment. When testing on a
connector with shorting bars, the shorting bars must be disabled to
ensure accurate test results. Insert an appropriate pick from EL-
38125-580 and depress the shorting bars above the appropriate
terminals. This will lift the shorting bar from the terminal and allow
accurate test results. Take care not to damage the connector, shorting
bar, or terminal when depressing the shorting bar.
- Test for infinite resistance between the two control circuits.
- If less than infinite resistance, repair the short between the two
circuits.
- If infinite resistance, replace the K36 Inflatable Restraint Sensing
and Diagnostic Module.
- Go to next step: If greater than 25 Ω
3. Ignition ON.
4. Test for less than 11 V between each control circuit terminal listed below on
the instrument panel harness
side of the connector and ground:
- X207 control circuit terminal 1
- X207 control circuit terminal 2
- X207 control circuit terminal 3
- X207 control circuit terminal 4
- If 11 V or greater
- Ignition OFF, disconnect the X1 harness connector at the K36 Inflatable
Restraint Sensing and
Diagnostic Module, ignition ON.
- Test for less than 1 V between each control circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K36 Inflatable Restraint Sensing and
Diagnostic Module.
- Go to next step: If less than 11 V
5. Ignition OFF.
6. Test for greater than 25 Ω between each control circuit terminal listed below
on the instrument panel
harness side of the connector and ground:
- X207 control circuit terminal 1
- X207 control circuit terminal 2
- X207 control circuit terminal 3
- X207 control circuit terminal 4
- If 25 Ω or less
- Disconnect the X1 harness connector at the K36 Inflatable Restraint
Sensing and Diagnostic
Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- If infinite resistance, replace the K36 Inflatable Restraint Sensing
and Diagnostic Module.
- Go to next step: If greater than 25 Ω
7. Install a 3 A fused jumper wire between the control circuit terminals
listed below on the instrument panel
harness side of the connector:
- F101 Passenger Instrument Panel Air Bag stage 1 X207 terminal 1 and 2
- F101 Passenger Instrument Panel Air Bag stage 2 X207 terminal 3 and 4
8. Ignition ON.
9. Verify the scan tool Deployment Loop Resistance parameter is less than 2 Ω.
- Ignition OFF, disconnect the X1 harness connector at the K36 Inflatable
Restraint Sensing and
Diagnostic Module.
- Test for less than 2 Ω in each control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K36 Inflatable Restraint Sensing and
Diagnostic Module.
- Go to next step: If less than 2 Ω
10. Ignition OFF, connect the X207 inline harness connector and disconnect
the appropriate X1 (DTC B0019)
or X2 (DTC B0020) harness connector at the F101 Passenger instrument panel air
bag, ignition ON.
11. Test for less than 11 V between each control circuit terminals listed below
and ground:
- F101 Passenger Instrument Panel Air Bag control circuit terminal 1 X1
- F101 Passenger Instrument Panel Air Bag control circuit terminal 2 X1
- F101 Passenger Instrument Panel Air Bag control circuit terminal 1 X2
- F101 Passenger Instrument Panel Air Bag control circuit terminal 2 X2
- If 11 V or greater
Repair the short to voltage on the circuit.
- Go to next step: If less than 11 V
12. Ignition OFF.
13. Test for greater than 25 Ω between each control circuit terminals listed
below and ground:
- F101 Passenger Instrument Panel Air Bag control circuit terminal 1 X1
- F101 Passenger Instrument Panel Air Bag control circuit terminal 2 X1
- F101 Passenger Instrument Panel Air Bag control circuit terminal 1 X2
- F101 Passenger Instrument Panel Air Bag control circuit terminal 2 X2
- If 25 Ω or less
Repair the short to ground on the circuit.
- Go to next step: If greater than 25 Ω
14. Install a 3 A fused jumper wire between the control circuit terminals
listed below:
- F101 Passenger Instrument Panel Air Bag stage 1 control circuit terminal
1 X1 and 2 X1
- F101 Passenger Instrument Panel Air Bag stage 2 control circuit terminal
1 X2 and 2 X2
15. Ignition ON.
16. Verify the scan tool Deployment Loop Resistance parameter is less than 2 Ω.
- Ignition OFF, disconnect the X1 harness connector at the K36 Inflatable
Restraint Sensing and
Diagnostic Module.
- Test for less than 2 Ω in each control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit
between the F101 Passenger
- Instrument Panel Air Bag connector and the X207 inline harness
connector.
- If less than 2 Ω, replace the K36 Inflatable Restraint Sensing and
Diagnostic Module.
- Go to next step: If less than 2 Ω
17. Ignition OFF, connect the harness connector at the F101 Passenger
Instrument Panel Air Bag, press in the
CPA (if equipped) until an audible and/or tactile click is heard.
18. Ignition ON, clear DTCs. Operate the vehicle within the Conditions for
Running the DTC.
19. Verify DTC B0019 or B0020 is not set.
- If DTC B0019 or B0020 is set
Test or replace the F101 Passenger Instrument Panel Air Bag.
- Go to next step: If DTC B0019 or B0020 is not set
20. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Instrument Panel Airbag Replacement
- SIR/SRS Wiring Repairs
- Control Module References for control module replacement, programming
and setup
READ NEXT:
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic
procedure: Diagnostic System Check
- Vehicle
Review the description of Strategy Based Diagnosis:Strateg
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
SEE MORE:
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
Diagnostic Fault
Warning:
Sitting in a reclined position when
the vehicle is in motion can be
dangerous. Even when buckled
up, the seat belts cannot do
their job.
The shoulder belt will not be
against your body. Instead, it will
be in front of you. In a crash, you
could go into it, receiving neck or
other injuries.