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 B101D 33: ECU Hardware Performance Special Memory Failure
DTC B101D 34: ECU Hardware Performance RAM Failure
DTC B101D 36: ECU Hardware Performance EEPROM Failure

### Circuit/System Description

When the ignition is turned ON, the radio performs a self test to verify if any critical malfunction exists within the system.

### Conditions for Running the DTC

This DTC runs continuously

### Conditions for Setting the DTC

The module has detected an internal electrical malfunction.

### Action Taken When the DTC Sets

Radio functions are disabled

### Conditions for Clearing the DTC

• | A current DTC clears when the conditions for setting the DTC are no longer present.

• | A history DTC clears after 50 malfunction-free ignition cycles.

### Reference Information

#### Schematic Reference

Radio/Navigation System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Radio/Audio 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 Verification

Verify that DTC B101D is not set.

⇒ | If the DTC is set, replace the radio.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio replacement, setup, and programming