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 B1424: Battery Voltage Low

### Circuit/System Description

With the ignition in either the ACC or ON positions, the theft deterrent module (TDM) should receive a 12V power supply. DTC B1424 will set to indicate the B+ positive supplied to the TDM is below the threshold.

### Conditions for Setting the DTCs

This DTC runs continuously once the following condition is met:

The supplied power to the TDM is between 9 - 16V.

### Action Taken When the DTC Sets

A warning lamp will illuminate.

### Conditions for Clearing the DTC

• | The condition for setting the DTC is no longer present.

• | The DTC can be cleared using a scan tool.

### Reference Information

#### Schematic Reference

Theft Deterrent System Schematics

#### Connector End View Reference

Component Connector End Views

#### Scan Tool Reference

Control Module References

### Circuit/System Testing

1. Ignition OFF, wait for 30 seconds.
2. Ignition ON, using the scan tool, select the DTC display function. Verify that DTC B1325 is set to current.
3. Ignition OFF, disconnect the TDM harness connector.
4. Ignition ON, test for B+ between the battery positive voltage circuit at the TDM harness connector and a known ground.

⇒ | If not within specified range, test the battery positive voltage circuit for an open/high resistance. If the circuit tests normal replace the TDM.

### Repair Instructions

Important: Always perform the Diagnostic Repair Verification .

Control Module References