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B0029


Schematic:






CIRCUIT DESCRIPTION
When you first turn ON the ignition, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. Then the SDM performs the following continuous diagnostic tests on the deployment loops:
^ Deployment loop voltage out of range test
^ Deployment loop resistance measurement test

If the voltage out of range test detects a short to voltage condition, the resistance measurement test for that deployment loop will not be performed.

CONDITIONS FOR RUNNING THE DTC
Deployment loop voltage out of range test:
^ Ignition 1 voltage is within the normal operating voltage range.
^ Passenger side deployment loop is not shorted to voltage.
^ Passenger side high terminal B4 is less than 2 Volts.

Deployment loop resistance measurement test:
^ Ignition 1 voltage is within the normal operating voltage range.
^ Passenger side deployment loop is not shorted to voltage.
^ Passenger side deployment loop is not shorted to ground.

CONDITIONS FOR SETTING THE DTC
Deployment loop voltage out of range test-Passenger side deployment loop resistance is at least 6 Ohms for 300 milliseconds.

Deployment loop resistance measurement test - Passenger side deployment loop resistance is more than 3.7 Ohms for 300 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
The SDM commands ON the AIR BAG warning lamp via Class 2 serial data.

CONDITIONS FOR CLEARING THE DTC
^ You can issue a CLEAR CODES command
^ A history DTC will clear once 255 malfunction free ignition cycles have occurred

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
^ The inflatable restraint passenger seat module yellow 2-way harness connector terminal A and terminal B.
^ The SDM wiring harness connector terminal B3 and terminal B4.
^ The wire to terminal connections in the passenger side high circuit.
^ The wire to terminal connections in the passenger side low circuit.
^ Refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION


Steps 1 - 6:





Steps 7 - 12:





The number(s) below refer to the step number(s) on the diagnostic table.
2. This step checks the inflatable restraint passenger seat module yellow 2-way connector.
5. This step checks to see if there is a malfunctioning inflatable restraint passenger seat module.
7. This step checks to see if there is an open or a high resistance in the passenger side high circuit.
9. This step determines if there is an open or a high resistance in the passenger side low circuit or if there is a malfunctioning SDM.