Circuit Description
When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.
Upon passing these tests, the ignition and deployment loop voltages are measured to ensure that these voltages are within the normal ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deployment loops.
The SDM tests the voltage continuously from the warning lamp terminal.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2502 Passenger Air Bag Disabled Indicator Circuit Malfunction
Conditions for Running the DTC
Ignition voltage is within the normal operating voltage range.
Conditions for Setting the DTC
| • | The passenger OFF indicator lamp does not turn ON when the ignition switch is turned ON. |
| • | The passenger OFF indicator lamp does not turn ON when the vehicle is running with no person on the passenger seat. |
Action Taken When the DTC Sets
The SDM commands the AIR BAG indicator ON.
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Caution: The sensing and the diagnosis module (SDM) can maintain sufficient voltage to deploy the airbags and pretensioners for up to 1 minute after the ignition has been turned OFF and the fuse has been removed. If the airbags and pretensioners are not disconnected, do not begin service until one minute has been passed after disconnecting power to the SDM. Failure to do so may cause personal injury.
Caution: Do not strike or jolt the inflatable restraint sensing and diagnostic module (SDM). Before applying power to the SDM, make sure that it is securely fastened with the arrow facing toward the front of the vehicle. Failure to observe the correct installation procedure could cause SIR deployment, personal injury, or unnecessary SIR system repairs.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 | Inspect the fuse F10. Is fuse F10 open? | -- | Go to Step 3 | Go to Step 4 |
3 | Replace the fuse F10. Did you complete the replacement? | -- | Go to Step 15 | -- |
4 |
Is the voltage within the indicated range? | 11-14 V | Go to Step 6 | Go to Step 5 |
5 | Repair the power supply and the wiring to the fuse F10. Did you complete the repair? | -- | Go to Step 15 | -- |
6 |
Is the bulb OK? | -- | Go to Step 8 | Go to Step 7 |
7 | Replace the bulb. Did you complete the replacement? | -- | Go to Step 15 | -- |
8 |
Is the voltage within the indicated range? | 11-14 V | Go to Step 10 | Go to Step 9 |
9 | Repair the wiring between the fuse F10 and the terminal 4 of the clock wiring connector. Did you complete the repair? | -- | Go to Step 15 | -- |
10 | Inspect the connection between terminal 4 and terminal 1 of the clock. Is the connection OK? | -- | Go to Step 12 | Go to Step 11 |
11 | Replace the clock assembly. Did you complete the replacement? | -- | Go to Step 15 | -- |
12 |
Is the voltage within the indicated range? | 11-14 V | Go to Step 13 | Go to Step 14 |
13 | Replace the SDM. Did you complete the replacement? | -- | Go to Step 15 | -- |
14 | Repair the wiring between the terminal 56 of the SDM and the instrument cluster. Did you complete the repair? | -- | Go to Step 15 | -- |
15 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
