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B1806



DTC B1806

CIRCUIT DESCRIPTION
The inflatable restraint inflatable restraint (I/P) module deployment loop consists of a dual stage inflatable restraint I/P module, the I/P module high and I/P module low circuits. There are 2 shorting bar used in the inflatable restraint I/P module connector which will short together the I/P module - high and I/P module low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing. When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (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 DTC will be stored.

DTC DESCRIPTORS
This diagnostic procedure supports the following DTCs:
- 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 Voltage

CONDITIONS FOR RUNNING THE DTC
Ignition 1 voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC
- DTC B1805 will set when the SDM detects a low resistance condition in the I/P module deployment loop.
- DTC B1806 will set when the SDM detects a high resistance condition in the I/P module deployment loop.
- DTC B1807 will set when the SDM detects a short to ground in the I/P module deployment loop.
- DTC B1808 will set when the SDM detects a short to voltage in the I/P module deployment loop.

ACTION TAKEN WHEN THE DTC SETS
The SDM commands the AIR BAG indicator ON.

CONDITIONS FOR CLEARING THE DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

DIAGNOSTIC AIDS
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.

The following are possible causes of the malfunction:
- A short between the I/P module - high and the I/P module - low circuits
- An open or high resistance in the I/P module - high or the I/P module - low circuits
- A short to ground in the I/P module - high or the I/P module - low circuits
- A short to voltage in the I/P module - high or the I/P module - low circuits
- A malfunctioning inflatable restraint I/P module
- An internal SDM malfunction

If an intermittent malfunction exists, refer to Diagnostic Aids for Circuit Testing and Wiring Repair procedures.

TEST DESCRIPTION

Steps 1 - 12:




Step 12:




The numbers below refer to the step numbers on the diagnostic table.
7. This step tests to see if the malfunction is caused by the inflatable restraint I/P module.
8. This step tests to see if the malfunction is caused by the inflatable restraint I/P module.
10. If DTC B1805 is present, test for a short between the I/P module high and I/P module low circuits.If DTC B1806 is present, test the I/P module high and I/P module low circuits for an open or high resistance.If DTC B1807 is present, test the I/P module high and I/P module low circuits for a short to ground.If DTC B1808 is present, test the I/P module high and I/P module low circuits for a short to voltage.