B0028

DTC B0028, B0029, or B0030









CIRCUIT DESCRIPTION
The inflatable restraint side impact module deployment loop consists of a side impact module, side impact module high control , and side impact module low control circuits. A shorting bar is used on the side impact module connector which will short together the side impact module high and side impact module low control 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 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 B0028 will set when the SDM detects the RF side impact module deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

-> DTC B0029 will set when one of the following conditions occurs:
- The SDM detects the RF side impact module deployment loop resistance is greater than 4.8 ohms for 500 milliseconds.
- The SDM detects the voltage at RF side impact module high control is less than 2.4 volts and RF side impact module deployment loop resistance is 6 ohms or greater for 500 milliseconds.

-> DTC B0030 will set when one of the following conditions occur:
- The SDM detects the voltage at RF side impact module high control is greater than 6 volts for 500 milliseconds.
- The SDM detects the voltage at RF side impact module high control is less than 2.4 volts and RF side impact 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.
-> You issue a scan tool CLEAR DTCs command.
-> A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
-> A short between the RF side impact module high and RF side impact module low control circuits.
-> An open or high resistance in the RF side impact module high or RF side impact module low control circuits.
-> A malfunctioning shorting bar on the RF side impact module connector.

Refer to Testing for Intermittent Conditions and Poor Connections.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. Inspects the RF side impact module in-line connector.
4. Tests for a malfunctioning RF side impact module.
7. If DTC B0028 is present, test for a short between the RF side impact module high and RF side impact low control circuits. If DTC B0029 is present, test for an open or high resistance in the RF side impact module high and RF side impact module low control circuits. If DTC B0030 is present, test for a short to ground or voltage in the RF side impact module high and RF side impact module low control circuits.