Audi A8 & S8 (2011-2018) MMI CD/DVD Player: A Guide to Component Protection and Replacement
Replacing the CD/DVD player in your D4-generation Audi A8 or S8 involves a critical anti-theft step called Component Protection that you cannot skip.
- Replacing this unit requires mandatory dealer or specialist programming to remove 'Component Protection', an anti-theft feature. This can cost $200-$500.
- A used unit is a cost-effective option, but you MUST buy a North American-spec part (e.g., 4H0035746x) and avoid Japanese-spec units (PR-code 8DZ or part number 4H0035678x).
- Failure can cause the entire MMI system to go black and lose sound because it is part of a fiber-optic loop.
- The physical replacement is DIY-friendly, but the final programming step is not. Factor the programming cost into your budget.
Symptoms of a Failing MMI CD/DVD Player
A problem with the MMI CD/DVD player can manifest in several ways, ranging from simple playback issues to problems that affect the entire infotainment system. Because it's part of a fiber-optic loop, a complete failure of this unit can bring down other MMI functions.
- CDs or DVDs Won't Play, Load, or Eject: The most common symptom is a mechanical failure of the drive itself. You may hear clicking or grinding noises, or the unit may simply refuse to accept or eject a disc.
- "Initializing Device" Message: The MMI screen may get stuck on a message like "Initializing Device, Please Wait..." when you select the CD player as a source.
- MMI System Freezes or is Unresponsive: A faulty CD player can cause the entire MMI system to lock up, freeze, or crash intermittently.
- Black MMI Screen or No Sound: In a total failure, the CD player can break the MOST fiber-optic loop. This open circuit prevents communication between MMI components, which can lead to a black screen and a complete loss of audio from all sources (radio, navigation, etc.). The system may power on briefly and then shut down.
Known Issues, TSBs, and Recalls
While there are no specific recalls from the National Highway Traffic Safety Administration (NHTSA) for the MMI CD/DVD player unit in the 2011-2018 Audi A8, A8 Quattro, or S8, the vehicles have been subject to other recalls for issues like passenger airbag sensors, engine compartment seals, and fuel lines. A Technical Service Bulletin (TSB), 2028446/7, was issued for a problem with the MMI screen's carrier mechanism, which could be resolved with a software update and a new carrier, but this does not pertain to the CD player itself. The primary known issue when replacing this unit is not a defect, but a feature: Component Protection.
The #1 Issue: Component Protection (CP)
Component Protection is an anti-theft system used by Audi. Nearly every major electronic module in the car, including the MMI CD/DVD player, is electronically linked to the vehicle's unique VIN at the factory. If you install a used part, the car will recognize that the serial number doesn't match its records and will activate Component Protection.
When CP is active on the MMI player, you will experience limited functionality. Typically, the unit will appear to work, but there will be no sound, or the sound will play for a second and then cut out. A message indicating "Component Protection Active" may also appear on the MMI screen. To remove Component Protection, the vehicle must be connected to Audi's online servers using a dealership-level diagnostic tool (like ODIS). This process verifies that the part is not from a stolen vehicle and pairs it to your car's VIN. This is not an optional step.
Buying a Used CD/DVD Player for Your A8 or S8
Given the extremely high cost of a new MMI unit from Audi, a used OEM part is the most practical solution for most owners. However, you must be very careful about what you buy.
How to Verify Compatibility
The most important step is to match the part number. The MMI unit is located in the glove box and must be removed to see the sticker with the part number.
- Correct Part Numbers for North America: Look for units with part numbers beginning with 4H0035746 or 4H0035670. The letter at the end indicates revisions (e.g., 4H0035746D, 4H0035746E, 4H0035670T). These are the correct units for the US/North American market.
- AVOID Japanese-Spec Units: The initial data for this part often includes part numbers like 4H0035678A, 4H0035678B, or 4H0035678C. These correspond to the vehicle option code PR-8DZ, which signifies a unit for the Japanese market. These units may have different radio tuners and navigation functionality that will not work correctly in North America. Do not purchase a unit with these part numbers or one advertised with option code 8DZ.
Pro Tip: When buying a used unit, always factor in the cost of Component Protection removal. A $100 used part is not a bargain if the dealer charges $400 to activate it. Call your local Audi dealer or a trusted European auto specialist beforehand to get a quote for this specific service.
Replacement Cost Breakdown
The cost to replace the MMI CD/DVD player varies dramatically depending on whether you buy a new or used part.
| Part/Service | Estimated Cost | Notes |
|---|---|---|
| New OEM Unit | $2,500 - $4,500+ | Extremely expensive. Prices vary by specific part number and revision. |
| Used OEM Unit | $75 - $250 | Widely available from online sellers and salvage yards. |
| Shop Labor (Installation) | $150 - $300 | Estimated 1.0-1.5 hours to remove the glove box and swap the unit. Independent shop rates are typically lower than dealer rates. |
| Component Protection Removal | $200 - $500 | This is a separate programming fee charged by a dealer or specialist with the correct online tools. It can be a flat fee or 1-2 hours of labor. |
Frequently Asked Questions (FAQ)
Can I replace the MMI CD player myself?
Yes, the physical replacement is a feasible DIY job for someone with moderate experience. It involves removing the glove box assembly to access the unit, which is held in by screws. You will also need a set of radio removal keys to slide the old unit out. However, you cannot complete the job yourself. After physical installation, the car MUST be taken to a dealer or specialist for Component Protection removal.
Can an independent mechanic remove Component Protection?
Some, but not all, can. Only shops that have invested in official diagnostic tools like ODIS (Offboard Diagnostic Information System) and have a subscription to Audi's online network (GeKo) can remove Component Protection. Always call and ask specifically if they can perform "Component Protection removal for an MMI unit" before bringing your car in. Many independent shops will refer this job to the dealer.
Is there any way to bypass Component Protection?
For the average owner, no. The only reliable method is having it professionally removed. There are highly technical, unsupported methods that involve desoldering the EEPROM chip from your original board and soldering it onto the replacement unit, but this is extremely risky and can destroy both modules if done incorrectly. It is not a recommended procedure.
Will a failed CD player set a Check Engine Light?
No, a faulty MMI component will not trigger the Check Engine Light, which is reserved for powertrain and emissions issues. It may, however, log fault codes in the infotainment control module (Address 5F) that can be read with a VAG-specific scan tool like VCDS or ODIS. A common fault code associated with this issue is P02095 (Component Protection Active).
Technical Specifications
OEM Part Numbers: 4H0035746A 4H0035746C 4H0035746D 4H0035746E 4H0035746F 4H0035746M 4H0035746N 4H0035670T 4H0035664B 4H0035664C 4H0035664CX
Part of MMI 3G+ System. Contains CD/DVD drive, dual SD card slots. Connects via MOST fiber-optic network.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Audi A8:
- Audi S8:
- Audi A8 Quattro: