Diagnostic Instructions
DTC Descriptors
DTC B1805: Passenger Air Bag Deployment Loop Resistance Too Low
DTC B1806: Passenger Air Bag Deployment Loop Resistance Too High
DTC B1807: Passenger Air Bag Deployment Loop Short to Ground
DTC B1808: Passenger Air Bag Deployment Loop Short to Battery
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 inflatable restraint module. There are 2 shorting bars used within
the module connector which will short together both high and low circuits, when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
B1805
The inflatable restraint module deployment loop resistance is low 5 times during primary check.
B1806
The inflatable restraint module high and/or low circuit is open for 2 seconds.
B1807
The inflatable restraint module high and/or low circuit is short to ground for 500 milliseconds.
B1808
The inflatable restraint module high and/or low circuit is short to voltage for 500 milliseconds.
Action Taken When the DTC Sets
• | The SDM commands the AIR BAG indicator ON. |
• | The SDM will store a DTC, however if an event occurs 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. |
Reference Information
Schematic Reference
SIR Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
SIR System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References 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 |
• | J 38715-XX Load Tool Adaptor |
Circuit/System Testing
Note: Refer to
SIR Service Precautions.
When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected
component/connector.
• | The inflatable restraint module |
• | The inflatable restraint module wiring harness connector |
• | The SDM wiring harness connector |
- Ignition OFF, disconnect the harness connector at the appropriate inflatable restraint module.
- With the appropriate adaptor, connect
J 38715-A
or
SA9409Z-A
in place of the inflatable restraint module.
- 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, replace the appropriate inflatable restraint module. |
- Ignition OFF, disconnect
J 38715-A
or
SA9409Z-A
and the appropriate adaptor.
- Disconnect the harness connector at the SDM.
- Ignition ON, test for less than 1 volt between I/P module Stage 1 terminal 2 and ground.
⇒ | If not within the specified range, test the circuit for a short to voltage. |
- Test for less than 1 volt between I/P module Stage 1 terminal 1 and ground.
⇒ | If not within the specified range, test the circuit for a short to voltage. |
- Ignition OFF, test for infinite resistance between I/P module Stage 1 terminal 2 and ground.
⇒ | If not within the specified range, test the circuit for a short to ground. |
- Test for infinite resistance between I/P module Stage 1 terminal 1 and ground.
⇒ | If not within the specified range, test the circuit for a short to ground. |
- Test for less then 1 ohm between I/P module Stage 1 terminal 2 and SDM terminal 4.
⇒ | If not within the specified range, test the circuit for an open/high resistance. |
- Test for less then 1 ohm between I/P module Stage 1 terminal 1 and SDM terminal 3.
⇒ | If not within the specified range, test the circuit for an open/high resistance. |
- If all circuits test normal, replace the SDM.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.