Mercedes Becker Radio Code
Mercedes-Benz fitted Becker-manufactured radios to its cars for decades, and millions of these units are still in daily use. If your Mercedes is displaying CODE — or, on older units, a flashing cursor waiting for input — after a battery change, you need the five-digit unlock code tied to the unit's BE serial number. This guide covers the Audio 10, Audio 20, Audio 50 and the older Audio 5 and Audio 10 CD families across the W202, W203, W204, W205, W169, W176, W210, W211, W212 and W213 chassis.
Why Mercedes Becker Radios Lock
Becker units fitted as OEM equipment in Mercedes vehicles use a power-loss trigger identical to other European manufacturers of the same era. When the permanent supply is cut — during a battery swap, jump-start, or even an extended storage period — the unit disables itself and demands the correct five-digit code. The code is unique to the serial number beginning with BE printed on the unit's label.
Note that some Becker COMAND and Audio 50 navigation systems are vehicle-bound rather than serial-coded — these units refuse to operate in any car other than the one they were built for, and a traditional code alone will not unlock them. See the COMAND article on our Mercedes brand page for details.
How to Find the BE Serial Number
The BE serial is printed on a white sticker on the casing of the unit. There are two ways to read it:
- On-screen display (Audio 20 and later): Switch the ignition on. If the display shows a code prompt, press and hold the AM/FM button or the 1 preset for several seconds. Some Audio 20 units show the serial in the display as part of their startup or diagnostic sequence. The format is
BE XXXXX XXXXX— write down the full 10-character segment after BE. - Unit extraction: Use DIN extraction hooks or, on later double-DIN COMAND/Audio 20 units, unscrew the surrounding trim to access the slide-out unit. The BE serial sticker is on the top or side. Prefix is always BE followed by digits and/or letters.
Entering the Five-Digit Mercedes Code
- Switch the ignition on (engine off is fine).
- Confirm the unit shows CODE or a flashing entry cursor.
- Use preset buttons 1, 2, 3, 4 to enter each digit in sequence. Each press of a button increments that digit position.
- Press the 5th preset button or the dedicated OK/confirm button to submit the five-digit code. Note: on some Audio 10 CD units, pressing * or SEND confirms entry.
- If correct, the display immediately shows the radio station or last source.
Order your code from our Mercedes brand page once you have the BE serial.
Becker Units Across Mercedes Generations
| Unit Name | Serial Prefix | Typical Chassis | Years |
|---|---|---|---|
| Audio 5 / Audio 10 | BE | W202, W210, W140 | 1993–2002 |
| Audio 10 CD | BE | W202, W203, W210 | 1998–2004 |
| Audio 20 | BE | W203, W204, W169, W245 | 2000–2014 |
| Audio 20 NTG4/4.5 | BE | W204, W205, W176, W246, C117 | 2007–2019 |
| Audio 50 / NTG2 | BE | W211, W220, W164 | 2002–2009 |
OEM manufacturers for these units are Becker and, for later NTG variants, Harman. The input method varies by chassis: older units use simple preset buttons; the Audio 20 NTG4.5 and NTG5 systems use a rotary controller similar to BMW's iDrive. On touchscreen-equipped NTG5 systems, code entry is performed on-screen.
Troubleshooting
- SAFE or CODE on older W202/W210: Normal code lock — retrieve the BE serial and order the code.
- WAIT: A wrong attempt was entered. Wait the displayed number of minutes (usually 60) before trying again.
- Unit is vehicle-bound (COMAND APS, later Audio 50 NTG2): Some COMAND units display a rejection message even with a valid code because they are paired to the vehicle's VIN. These require dealer-level reprogramming.
- Serial reads BE followed by nothing: Some early units have a two-part serial split across two lines of the label. Read both lines together as a single string.
- Code accepted but radio cuts out immediately: This is usually an aerial or CAN-bus issue unrelated to the code lock.
Frequently Asked Questions
Is the Mercedes Becker code always five digits?
Yes. All Becker-manufactured OEM Mercedes units use a five-digit unlock code, unlike VW/Audi (four digits) or Ford (five digits via a different algorithm).
My W204 C-Class shows CODE 1234 — what does that mean?
This is the starting display position for code entry, showing four placeholders. It is not the actual code. Use your preset buttons to change each digit to match the code you have been given.
The BE serial on my unit has only eight characters total — is that right?
Some older Becker units have shorter serial strings. Enter the full string as printed, including the BE prefix.
Can the code be retrieved from the vehicle's VIN?
Mercedes dealers can sometimes look up the original code using the VIN if factory records are available. For second-hand vehicles or imported cars, serial-based ordering is more reliable.
Will a wrong entry permanently damage the radio?
No. Multiple wrong entries trigger a timed lockout (typically one hour), not permanent damage. After the wait period, try again carefully.