For 1990-2009 cars

### 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 SDM itself.

These test ignition and deployment loop voltages are measured to ensure that they are within their normal voltage 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.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1101 Battery Voltage High

### Conditions for Running the DTC

Ignition voltage is within the normal operating voltage range.

### Conditions for Setting the DTC

The voltage supplied from the battery is over 16.5 volts.

### 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 | Yes | No
--- | --- | --- | ---
Warning: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Warning in the Preface section. Warning: Refer to Sensing and Diagnostic Module Handling Warning in the Preface section. Schematic Reference: SIR Schematics Connector End View Reference: Component Connector End Views
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Inspect the vehicle's charging system including the alternator. Is the charging system OK? | Go to Step 4 | Go to Step 3
3 | Repair the charging system. Is the repair complete? | Go to Step 5 | --
4 |

1. Disconnect the negative battery cable.
2. Replace the sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement.

Is the repair complete?

Go to Step 5

--

5 |

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

Does the DTC reset?

Go to Step 2

System OK