B0018

CIRCUIT DESCRIPTION
The dual stage inflatable restraint IP module deployment loop consists of the dual stage inflatable restraint IP module, and the IP module high and low circuits for both stages 1 and 2. Two shorting bars used within the IP module connector short together both the IP module stage 1 high and low circuits, and the IP module stage 2 high and low circuits when the connector is disconnected. This helps to prevent unwanted deployment of the inflator module during servicing. During a frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) allows current to flow through the deployment loop in order to deploy the IP module. When the ignition is turned ON, the 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 diagnostic trouble code (DTC) will be stored in memory.

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

CONDITIONS FOR SETTING THE DTC
- DTC B0012 in stage 2 or B0016 in stage 1 will set when the IP module deployment loop resistance is less than 1.3 ohms for 500 milliseconds
- DTC B0013 stage 2 or B0017 in stage 1 will set when one of the following conditions occurs:
- IP module high circuit is less than 2.4 volts and the IP module deployment loop is more than 6 ohms for 500 milliseconds.
- IP module deployment loop resistance is more than 4.8 ohms for 500 milliseconds.
- DTC B0014 in stage 2 or B0018 in stage 1 will set when one of the following conditions occur:
- IP module high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
- IP module high circuit is less than 2.4 volts and IP module deployment loop resistance is less than 6 ohms for 500 milliseconds.

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

CONDITIONS FOR CLEARING THE DTC
- The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
- A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
The following are possible causes of the malfunction:
- A short between the IP module stage 1 or stage 2, high and low circuits.
- An open or a high resistance in the IP module stage 1 or stage 2, high or low circuits.
- A short to ground or a short to voltage in the IP module stage 1 or stage 2, high or low circuits.
- The IP module connector
- The SDM connector
- A malfunctioning IP module
- A malfunctioning SDM

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

TEST DESCRIPTION

Steps 1-3:

Steps 4-5:

Steps 5-9:

The numbers below refer to the step numbers on the diagnostic table.
4. Tests to see if the malfunction is caused by the IP module.
6. Tests to see what DTCs are present. If DTC B0012 or B0016 is present, test the IP module for a short between high and low circuits in stage 1 or stage 2. If DTC B0013 or B0017 is present, test the IP module high and low circuits for an open and for high resistance in stage 1 or stage 2. If DTC B0014 or B0018 is present, test the IP module high and low circuits for a short to ground and for a short to voltage in stage 1 or stage 2.