Supplemental Inflatable Restraint (SIR)

Wiring Diagram:

CIRCUIT DESCRIPTION
When there is an open in the driver inflator module or the SIR coil assembly, the resistance between "Driver Side High" terminal "B9" and "Driver Side Low" terminal "B8," increases. This causes a larger voltage drop from the "Driver Side High" to the "Driver Side Low" across a resistor inside the DERM which connects these two terminals together. The increase in the voltage difference between "Driver Side High" and "Driver Side Low" is detected by the DERM during the "Continuous Monitoring" tests and DTC 26 is set.

DTC WILL SET WHEN
The voltage difference between "Driver Side High" terminal "B9" and "Driver Side Low" terminal "B8" is above or equal to a specified value for 500 milliseconds.

ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets a diagnostic trouble code.

DTC WILL CLEAR WHEN
The voltage difference between "Driver Side High" terminal "B9" and "Driver Side Low" terminal "B8" is below a specified value for 500 milliseconds.

DTC TABLE TEST DESCRIPTION
Number(s) below refer to step number(s) on the diagnostic table.
1. The "SIR DIAGNOSTIC SYSTEM CHECK" must be the starting point for all diagnostics.
7. This test determines if a steering column malfunction is occurring.
8. This test determines if the malfunction is occurring in the inflator module or the SIR coil assembly.

DIAGNOSTIC AIDS
This diagnostic trouble code will only set when there is an improper connection of either the yellow 2-way connector at the base of the steering column or the yellow 2-way connector at the top of the steering column an open SIR coil assembly or an open inflator module.