Supplemental Inflatable Restraint (SIR)

CIRCUIT DESCRIPTION
Code 23 is set when the voltage at the "Sense Low" input, Terminal "A6," is greater than a specific percentage of "36 VLR" output voltage for 500 milliseconds during the "Continuous Monitoring" tests performed by the DERM. The "Continuous Monitoring" tests are performed by the DERM after the initial "Turn-On" tests are completed and are performed every 100 milliseconds while "Ignition 1" voltage is present at the DERM. The "Continuous Monitoring" tests check the continuity of the deployment loop from the "36 VLR" output of the DERM through the arming sensor, inflator module and the discriminating sensors to ground. Code 23 indicates a shorted arming sensor, short to the "36 VLR," or an open in the low side of the deployment loop.

TEST CONDITIONS
Tested every 100 milliseconds during "Continuous Monitoring."

FAILURE CONDITIONS
Code 23 will set if the voltage at the "Sense Low" input, Terminal "A6," is greater than a specific percentage of "36 VLR" output voltage for 500 milliseconds.

ACTION TAKEN
DERM turns "On" the "Air Bag" telltale lamp.

CONDITIONS TO CLEAR
Cycle Code 23 will clear if the voltage at the "Sense Low" input, terminal "A6," is within a specific range of "36 VLR" Output voltage for 500 milliseconds (five consecutive "Continuous Monitoring" cycles) after Code 23 has been set.

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the integrity of the low side of the deployment loop between the steering column and the driver side discriminating sensor.
2. This test checks for an open in the driver side discriminating sensor between terminal "A" and the splice.
3. This test checks for a short from the "36 VLR" circuit to the "Force High" circuit.
4. This test checks for a short from the "36 VLR" circuit to the "Sense Low" circuit.
5. This test checks for a short from the "36 VLR" circuit to the "Force Low" circuit.
6. This test checks for a short from the "36 VLR" circuit to Circuit 347.
7. This test checks for a short from the "36 VLR" circuit to Circuit 348 or Circuit 349.
8. The code is being set by an arming sensor which is latched closed, a partial short across the arming sensor diagnostic resistor or a faulty DERM.