DTC 15

Circuit Description
When the ignition switch is turned ON, the sensing and diagnostic module (SDM) will perform tests to diagnose critical malfunctions within itself. Upon passing these tests, Ignition 1 and deployment loop voltages are measured to ensure that they are within their respective normal voltage ranges. The SDM then proceeds with the resistance measurement test. Passenger low terminal 4 is grounded through a current sink. The passenger current source is connected to the passenger high terminal to allow a known amount of current to flow. By monitoring the voltage difference between passenger high and passenger low, the SDM calculates the combined resistance of the passenger inflator module, harness wiring, and connector terminal contacts.

DTC 15
Diagnostic Trouble Code (DTC) 15 will set when the combined resistance of the passenger deployment loop is above a specified value. The test is run once each ignition cycle during the resistance measurement test when the following conditions occur:
- No higher priority faults are detected when the ignition is turned ON.
- Ignition 1 voltage is above a specified value.

When DTC 15 is set, the SDM will turn ON the AIRBAG indicator.
DTC 15 will clear when the following conditions occur:
- The ignition switch is turned OFF.
- The scan tool CLEAR CODES command is received.

Test Description
The numbers below refer to steps on the diagnostic table.

2. Refer to the first caution below.
8. Refer to the cautions below.

Diagnostic Aids
An intermittent condition is likely to be caused by a poor connection at the passenger inflator module harness connector terminals, SDM terminals 1 or 4, or poor wire-to-terminal connections in that circuit. The test for this DTC is run only while the AIRBAG indicator is performing the bulb test. When a scan tool CLEAR CODES command is issued and the malfunction is still present, the DTC will not reappear until the next ignition cycle.

Steps 1 - 7:

Steps 8 - 10:

DTC 15 - Passenger Deployment Loop Resistance High

CAUTION: The sensing and diagnostic module (SDM) can maintain sufficient voltage to deploy the airbags for 10 minutes after the ignition is OFF and the fuse has been removed. If the airbags are not disconnected, do not begin service until 10 minutes have passed after disconnecting power to the SDM. Otherwise, injury could result.

CAUTION: Never measure the resistance of an inflator module with an ohmmeter. The ohmmeter battery could unexpectedly deploy the airbag which would created the possibility of severe injury and would require the replacement of otherwise useable components.

CAUTION: During service procedures, be very careful when handling the SDM. Never strike or jar the SDM. Never power the supplemental inflatable restraints (SIR) system when the SDM is not rigidly attached to the vehicle. All SDM mounting bolts must be carefully tightened, and the SDM arrow must be pointing toward the front of the vehicle to ensure proper operation of the SIR system. The SDM could be activated if it is powered when it is not rigidly attached to the vehicle, resulting in unexpected deployment and possible injury.