For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC B0053 : Deployment Commanded with Loop DTCs Present

### Circuit/System Description

The inflatable restraint sensing and diagnostic module (SDM) contains a sensing device that converts changes in vehicle velocity to an electrical signal. The SDM compares this signal to a value stored in memory. When the generated signal exceeds the stored value, the SDM performs additional signal processing and compares the generated signals to values stored in memory. When 2 of the generated signals exceed the stored values, the SDM will cause current to flow through the inflator modules, deploying the air bags. DTC B0053 will set instead of DTC B0051 when a deployment occurs while an inflator circuit fault is present that may result in a non-deployment situation in one or more of the inflator modules.

### Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

### Conditions for Setting the DTC

Ignition voltage must be present and the SDM must have commanded an air bag deployment with faults present.

### Action Taken When the DTC Sets

• | The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.

• | The SDM records crash data.

### Conditions for Clearing the DTC

DTC B0053 is a latched code. A latched code cannot be cleared. Replace the SDM after following the instructions in the circuit/system testing.

### Reference Information

#### Schematic Reference

SIR Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

SIR System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

Important: The seat belt pretensioners may deploy for impacts that are not severe enough to warrent frontal or side air bag deployment. The SDM is capable of sustaining 3 pretensioners deployment events or one frontal or side deployment event. After the maximum number of deployments has occurred, DTC B0053 sets and becomes a latched code, which cannot be cleared.

When DTC B0053 is accompanied by additional DTCs, other than B0051, repair the malfunction causing the other DTCs before replacing the SDM.

1. Ignition OFF, verify no signs of inflator module or pretensioner deployment exists.

⇒ | If any signs of deployment exists, refer to Repairs and Inspections Required After a Collision.

2. Verify the DTC B0053 is not set.

⇒ | If the DTC is set, clear the DTC. If the DTC resets, replace the SDM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | SIR/SRS Wiring Repairs

• | Control Module References for SDM replacement, setup, and programming