B1025

NOTICE: When DTC B1025 has been set it is necessary to replace the Inflatable restraint Sensing and Diagnostic Module (SDM). Setting DTC B1025 will also cause DTC B1071 to set. When a scan tool clear codes command is issued and the malfunction is no longer present, DTC B1025 and DTC B1071 will remain current. Ensure that the short to B+ condition is repaired prior to installing a replacement SDM to avoid damaging the SDM.

When measurements are requested in this table, use J 39200 DMM with the correct terminal adapter from J 35616-A Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Diagram Information in Diagrams. When a wire, connector, or terminal repair is requested, use J 38125-A Terminal Repair Kit and refer to Wiring Repair.

CIRCUIT DESCRIPTION
When you first turn the ignition switch to the ON position, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. Upon passing these tests IGNITION 1, 23 VLR and deployment loop voltages are measured to make sure they are within their respective normal voltage ranges. The SDM monitors the voltages at DRIVER SIDE LOW terminal 10 and PASSENGER SIDE LOW terminal 3 to detect shorts to B+ in the inflator module circuits. The service wait time is 10 minutes. Refer to Air Bag(s) Arming and Disarming procedures.

CONDITIONS FOR SETTING THE DTC
^ The voltage at PASSENGER SIDE LOW terminal 3 is less than 3.5 volts,
^ The voltage at DRIVER SIDE LOW terminal 10 is more than 3.5 volts for 500 milliseconds.

The CONTINUOUS MONITORING test checks for this DTC. This test occurs when IGNITION 1 is within the normal operating voltage range.

ACTION TAKEN WHEN THE DTC SETS
^ The SDM sets DTC B1025 and also DTC B1071.
^ The SDM turns ON the AIR BAG warning lamp.

CONDITIONS FOR CLEARING THE DTC
DTC B1025 is a latched code. You cannot clear a latched code. Repair the malfunction that set this DTC before you replace the SDM.

DIAGNOSTIC AIDS
A short-to-B+ in the inflatable restraint steering wheel module circuit can cause an intermittent condition. A DTC B1025 would be accompanied by DTC B1071. Inspect CKTs G/R and G carefully for cutting or chafing. A careful Inspection of the circuits and components indicated on the DTC B1025 Table is essential to make sure that the replacement SDM will not be damaged. The diagnostic table directs the technician to note the entry value of DRIVER SENSELO. Comparing the value of DRIVER SENSELO can be helpful in determining if an intermittent condition exists.

DTC TABLE TEST DESCRIPTION
Numbers below refer to step numbers on the diagnostic table.
2. This test determines the DRIVER SIDE LOW voltage measured by the inflatable restraint Sensing and Diagnostic Module (SDM).
3. This test isolates the malfunction to one side of the inflatable restraint steering wheel module coil yellow 2-way connector located near the base of the steering column.
4. This test determines whether the malfunction is in the inflatable restraint steering wheel module coil or the inflatable restraint steering wheel module.
7. This test determines whether the malfunction is in CKT G/R.
9. This test determines whether the malfunction is m CKT G.