For 1990-2009 cars

## DTC B2502 Except North America Vehicles

### 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.

The SDM continuously checks the cut-off switch position and circuit defect by letting voltage flow through the cut-off switch circuit.

### 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 blink properly.

### 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.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section. Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section. Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views
1 | Did you perform a Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Confirm that the ignition switch is OFF.
2. Visually inspect the wiring and connector of the passenger airbag disable switch.

Is the wiring damaged or the connector disconnected?

--

Go to Step 3

Go to Step 4

3 | Repair the wiring or connect the connector. Did you complete the repair? | -- | Go to Step 13 | --
4 |

1. Remove the clock assembly.
2. Check the bulb of the passenger airbag off lamp.

Is the bulb OK?

--

Go to Step 6

Go to Step 5

5 | Replace the bulb of the passenger airbag off lamp. Did you complete the replacement? | -- | Go to Step 13 | --
6 | Inspect the connection between terminal 6 and 10 of the clock. Is the connection OK? | -- | Go to Step 8 | Go to Step 7
7 | Replace the clock. Did you complete the replacement? | -- | Go to Step 13 | --
8 |

1. Confirm that the ignition switch is ON.
2. Measure the voltage from terminal 6 of the clock wiring connector.

Is the voltage within the indicated range?

4.75-5.25 V

Go to Step 10

Go to Step 9

9 | Repair the wiring between the terminal 56 of the SDM and terminal 6 of the clock wiring connector. Did you complete the repair? | -- | Go to Step 13 | --
10 |

1. Disconnect the connector of the passenger airbag disable switch.
2. Measure the resistance between terminal 10 of the clock and terminal 1 of the disable switch.

Is the resistance as specified?

0 ohms

Go to Step 12

Go to Step 11

11 | Replace the wiring between terminal 10 of the clock and terminal 1 of the disable switch. Did you complete the repair? | -- | Go to Step 13 | --
12 | Replace the SDM. Did you complete the replacement? | 11-14 V | Go to Step 13 | --
13 |

1. Reconnect all SIR system components.
2. Verify that all components, connectors, and connector position assurances (CPAs) are properly mounted.
3. Use the scan tool to clear the DTCs.
4. Operate the vehicle within the Conditions for Running the DTC as specified in the text.

Does the DTC reset?

--

Go to Step 2

System OK

## DTC B2502 North America Vehicles

### 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 operate depending on the status of passenger presence.

### 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.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section. Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section. Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views
1 | Did you perform a Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Inspect the fuse F3. Is fuse F3 blown? | -- | Go to Step 3 | Go to Step 4
3 | Replace the fuse F3. Did you complete the replacement? | -- | Go to Step 15 | --
4 |

1. Confirm that the ignition switch is ON.
2. Remove the clock assembly.
3. Measure the voltage from the fuse F3.

Is the voltage within the indicated range?

9-14 V

Go to Step 6

Go to Step 5

5 | Repair the power supply and the wiring to the fuse F3. Did you complete the repair? | -- | Go to Step 15 | --
6 |

1. Confirm that the ignition switch is OFF.
2. Remove the clock.
3. Inspect the bulb of the passenger air bag ON indicator.

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 |

1. Confirm that the ignition switch is ON.
2. Measure the voltage from terminal 1 of the clock wiring connector.

Is the voltage within the indicated range?

9-14 V

Go to Step 10

Go to Step 9

9 | Repair the wiring between the fuse F3 and the terminal 1 of the clock wiring connector. Did you complete the repair? | -- | Go to Step 15 | --
10 | Inspect the connection between terminal 1 and terminal 10 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 |

1. Confirm that the ignition switch is OFF.
2. Disconnect the sensing and diagnostic module (SDM) connector.
3. Confirm that the ignition switch is ON.
4. Measure the resistance between terminal 56 of the SDM and terminal 10 of the clock connector.

Is the resistance as specified?

0 ohms

Go to Step 13

Go to Step 15

13 | Measure the resistance between terminal 56 of the SDM and ground. Is the resistance as specified? | ∞ | Go to Step 14 | Go to Step 15
14 | Replace the SDM. Did you complete the replacement? | -- | Go to Step 16 | --
15 | Repair the wiring between the terminal 56 of the SDM and the clock. Did you complete the repair? | -- | Go to Step 16 | --
16 |

1. Reconnect all SIR system components.
2. Verify that all components, connectors, and connector position assurances (CPAs) are properly mounted.
3. Use the scan tool to clear the DTCs.
4. Operate the vehicle within the Conditions for Running the DTC as specified in the text.

Does the DTC reset?

Go to Step 2

System OK