B0019
DTC B0019 or B0020
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0019 01
- Passenger Frontal Deployment Loop Stage 1 Short to Battery
DTC B0019 02
- Passenger Frontal Deployment Loop Stage 1 Short to Ground
DTC B0019 04
- Passenger Frontal Deployment Loop Stage 1 Open Circuit
DTC B0019 0D
- Passenger Frontal Deployment Loop Stage 1 Resistance Above Threshold
DTC B0019 0E
- Passenger Frontal Deployment Loop Stage 1 Resistance Below Threshold
DTC B0020 01
- Passenger Frontal Deployment Loop Stage 2 Short to Battery
DTC B0020 02
- Passenger Frontal Deployment Loop Stage 2 Short to Ground
DTC B0020 04
- Passenger Frontal Deployment Loop Stage 2 Open Circuit
DTC B0020 0D
- Passenger Frontal Deployment Loop Stage 2 Resistance Above Threshold
DTC B0020 0E
- Passenger Frontal Deployment Loop Stage 2 Resistance Below Threshold
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 appropriate deployment loop in order to deploy the passenger instrument panel (I/P) inflator module at the correct stage. Shorting bars are located in the electrical connectors of both the stage 1 deployment loop and the stage 2 deployment loop of the I/P module. The I/P module high control circuit and low control circuit are shorted together by the shorting bar when the electrical connector is disconnected. The shorting bars help prevent unwanted deployment of the inflator module during servicing.
The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If the results of any deployment loop circuit test is below specification, DTC B0019 or B0020 and the appropriate symptom byte sets.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
B0019 01 or B0020 01
The inflatable restraint module high and/or low circuit is short to voltage for 120 milliseconds.
B0019 02 or B0020 02
The inflatable restraint module high and/or low circuit is short to ground for 120 milliseconds.
B0019 04 or B0020 04
The inflatable restraint module high and/or low circuit is open for 120 milliseconds.
B0019 0D or B0020 0D
The inflatable restraint module deployment loop resistance is greater than 3.9 ohms for 120 milliseconds.
B0019 0E or B0020 0E
The inflatable restraint module deployment loop resistance is less than 1.1 ohms for 120 milliseconds.
Action Taken When the DTC Sets
* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator and display the message "Service Air Bag."
* The SDM 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 Aids
If DTC B0019 0E or B0020 0E is setting, be certain that all circuit shorting bars are isolated after connecting circuit components. There are shorting bars in most circuit connectors, including the SDM and inline harness connectors. DTC B0012 0E or B0013 0E will set if the shorting bars are engaged when the ignition is ON.
Reference Information
Schematic Reference
SIR Schematics ([1][2]Air Bag Systems)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
SIR System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
Each inflatable restraint module requires a specific adapter to connect the load tool to the SIR system.
* J 38715-A Driver and Passenger SIR Load Tool
* SA9409Z-A SIR Load Tool (Driver/Passenger/Curtain)
Circuit/System Testing
Important: When removing the connectors, inspect for terminal damage or corrosion. Inspect the connector body for damage to the locators that disengage the shorting bars when connected. Damage or corrosion to the following components requires repair or replacement of the affected component/connector:
* Inflatable restraint module
* SDM module
* Front end sensor wiring harness connector
* SDM wiring harness connector
Important: 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. Correct connection isolates the shorting-bars within the connector allowing the deployment circuit to operate properly.
1. Verify that the inflatable restraint passenger I/P module connector and CPA are engaged.
• If the above condition is not found, make the appropriate repair.
2. Ignition OFF, disconnect the harness connector at the I/P module.
3. With the appropriate load tool adapter, connect J 38715-A or SA9409Z-A in place of the I/P module.
4. Ignition ON, with a scan tool, verify the appropriate DTC is set as current.
• If the DTC is not set or is set as history, cycle the ignition OFF, disconnect the load tool and adapter, reconnect the harness connector at the I/P module, and cycle the ignition ON. If the DTC resets after reconnecting the module, replace the I/P module.
5. Ignition OFF, disconnect the load tool and the adapter.
6. Disconnect the harness connector at the SDM.
7. Ignition ON, test for less than 1.0 volt between the appropriate control circuit listed below and ground:
* I/P module Stage 1 terminal 18
* I/P module Stage 1 terminal 19
* I/P module Stage 2 terminal 12
* I/P module Stage 2 terminal 13
• If not within the specified range, test the control circuit for a short to voltage.
8. Ignition OFF, test for infinite resistance between the appropriate control circuit terminal listed below and ground:
* I/P module Stage 1 terminal 18
* I/P module Stage 1 terminal 19
* I/P module Stage 2 terminal 12
* I/P module Stage 2 terminal 13
• If not within the specified value, test the control circuit for a short to ground.
9. Test for less then 1.0 ohm between the appropriate control circuit terminal listed below:
* I/P module Stage 1 terminal A and SDM terminal 18
* I/P module Stage 1 terminal B and SDM terminal 19
* I/P module Stage 2 terminal A and SDM terminal 13
* I/P module Stage 2 terminal B and SDM terminal 12
• If not within the specified range, test the control circuit for an open/high resistance.
10. If all circuits test normal, replace the SDM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Instrument Panel Inflatable Restraint Module Replacement (Service and Repair)
* SIR/SRS Wiring Repairs (Component Tests and General Diagnostics)
* Control Module References (Programming and Relearning) for SDM replacement, setup, and programming