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 B1243 00: CD-Player Load or Unload Performance
DTC B1248 00: CD Changer Load/Unload mechanism Performance

### 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

The CD player/changer recovers from loading/ejecting error.

### Conditions for Setting the DTC

The CD player/changer experiences a loading/ejecting error.

### Action Taken When the DTC Sets

The radio displays a "Mechanism Error" message temporarily.

### Conditions for Clearing the DTC

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

• | The history DTC will clear after 50 fault-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

1. Ignition ON, with a scan tool clear all DTCs.
2. Radio ON, play a known good CD. Eject and reinsert the CD several times and verify B1243 or B1248 does not reset.

⇒ | If the DTC resets, replace the radio.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio replacement, setup, and programming