For 1990-2009 cars

### Circuit Description

Internal defects in theTheft Deterrent Module (TDM) set DTC 55.

### Conditions for Setting the DTC

Theft Deterrent Module hardware failure (EEPROM, RAM, ROM defective).

### Action Taken When the DTC Sets

The engine will not start.

### Conditions for Clearing the DTC

• | Replacing the Theft Deterrent Module.

• | A history DTC will clear after 20 consecutive ignition cycles if the condition for the fault is no longer present.

• | Using a scan tool.

### Diagnostic Aids

Test the power and ground circuits before replacing the module.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. Replacing the module is the only way to repair the condition.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Theft Deterrent Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Theft Deterrent
2 | Replace the Theft Deterrent Module. Did you complete the replacement? | -- | System OK | --