Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2004 Ford Explorer 4.0 E, AWDFACTORY OEM SERVICE PROCEDURE
Entertainment System DTCS
AUDIO UNIT DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Description | Source | Perform Test |
|---|---|---|---|
| B1342 | ECU Is Defective | Audio Unit | CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B1342 is retrieved again, REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| B2401 | Audio Tape Deck Mechanism Fault | Audio Unit | VERIFY that no cassette is inserted in the audio unit. CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B2401 is retrieved again, REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| B2402 | Audio Compact Disc/Disc Jockey Thermal Shutdown Fault | Audio Unit | Not applicable if CD6. CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B2402 is retrieved again, REMOVE the CD unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| B2403 | Audio Compact Disc/Disc Jockey Internal Fault | Audio Unit | If equipped with CDDJ, CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B2403 is retrieved again, REMOVE the CD unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| B2405 | Audio Single-Disc CD Player Thermal Shutdown Fault | Audio Unit | CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B2405 is retrieved again, REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| B2406 | Audio Single-Disc CD Player Internal Fault | Audio Unit | CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC B2406 is retrieved again, REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
| U2003 | Audio Compact Disc/Disc Jockey Is Not Responding | Audio Unit | If equipped with Compact Disc/Disc Jockey, CLEAR and DOCUMENT the DTCs. CARRY OUT the self-test. If DTC U2003 is retrieved again, REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation. |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.