When the ignition switch is first turned to the RUN position, the IGN 1 Fuse applies battery voltage to the AIR BAG warning lamp that is connected to the INFLATABLE RESTRAINT INDICATOR, terminal 6. The SIR Fuse applies battery voltage to the IGNITION input, terminal 5. The inflatable restraint sensing and diagnostic module (SDM) responds by flashing the AIR BAG warning lamp seven times. If IGNITION is outside of the normal operating voltage range (9 volts - 16 volts), the AIR BAG warning lamp will come ON solid with no DTCs set.
In order to disable the shorting bar from terminal 6 to terminal 7 inside the inflatable restraint sensing and diagnostic module (SDM) harness connector, the SDM harness connector must be properly connected to the SDM.
When measurements are requested in this table, use J 39200 Digital Multimeter with the correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections . When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair .
The numbers below refer to the step numbers on the diagnostic table:
This step checks to see if sufficient IGNITION voltage applied to the SDM.
This step checks to see if IGNITION voltage applied to the SDM.
This step checks to see if the connector position assurance (CPA) is properly installed.
This step determines if the SDM is turning ON the AIR BAG warning lamp or if there is a malfunctioning SDM.
This step checks to see if the shorting bar is damaged.
This step checks to see if there is a short to ground CKT 358.
This step checks to see if there is a short between CKT 358 and CKT 1751 or if there is a short to ground in CKT 358.
This step checks to see if the SIR Fuse is open. An open SIR Fuse would cause the AIR BAG warning lamp to come on steady.
This step checks to see if the short to ground caused the SIR Fuse to open.
This step checks for a short to ground in CKT 1751.
This step checks to see if the SDM wiring harness connector properly secures to the SDM.
This step checks to see if there is an open in CKT 1139.
This step determines if there is an open or a high resistance in the B+ feed circuit to the input side of the SIR Fuse or if there is a malfunctioning SDM.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Is the ignition voltage more than the specified value? | 9 V | |||
Is the ignition voltage more than the specified value? | 16 V | Go to Battery Is Undercharged or Overcharged in Engine Electrical | ||
Is the SDM CPA properly installed? | -- | |||
5 | Properly install the CPA. Is the repair complete? | -- | -- | |
Does the AIR BAG warning lamp come ON steady? | -- | |||
Is the shorting bar damaged or corroded? | -- | |||
8 | Replace the SDM wiring harness connector. Refer to Wiring Repair . Is the repair complete? | -- | -- | |
Is the measured resistance less than the specified value? | OL | |||
Is the measured resistance less than the specified value? | OL | |||
11 |
Is the repair complete? | -- | -- | |
12 |
Is the repair complete? | -- | -- | |
13 | Replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console. Is the repair complete? | -- | -- | |
Is the SIR Fuse good? | -- | |||
Is the SIR Fuse good? | -- | |||
Is the measured resistance less than the specified value? | OL | |||
17 |
Is the repair complete? | -- | -- | |
18 | Install the SIR Fuse. Is the repair complete? | -- | -- | |
Inspect the SDM wiring harness connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the connector secure? | -- | |||
20 |
Is the repair complete? | -- | -- | |
21 |
Is the SDM wiring harness connector terminal 5 damaged or corroded? | -- | ||
22 | Replace the SDM wiring harness connector. Refer to Wiring Repair . Is the repair complete? | -- | -- | |
23 | Inspect the SDM terminals for damage or corrosion. Are any terminals damaged or corroded? | -- | ||
24 | Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement Is the repair complete? | -- | -- | |
Use the J 39200 to measure the resistance between the output side of the SIR Fuse and terminal 5 of the SDM wiring harness connector. Is the measured resistance within the specified value? | 0-2 ohms | |||
26 |
Is the repair complete? | -- | -- | |
Is the measured voltage within the specified value? | B+ | Go to Power Distribution Schematics in Wiring Systems | ||
28 | Reconnect all the SIR system components, make sure all the components are properly mounted. Have all the SIR components been reconnected and properly mounted? | -- | -- |