Becker Radio Code Guide

Becker is one of Europe's oldest and most respected car radio manufacturers, supplying OEM units to Mercedes-Benz, Porsche, and Audi for decades before being absorbed into the Harman International group. If your radio shows a blank code entry prompt — or the classic Becker five-digit entry display — and it carries a BE serial number, this guide explains how to find it and enter your unlock code.

Which Vehicles Use Becker OEM Radios?

Mercedes-Benz

Becker was the primary Mercedes OEM radio supplier from the 1970s to the 2010s. Becker-built units appear in virtually every Mercedes class built before the widespread adoption of Harman's own systems:

• C-Klasse W202 / W203 / W204 / W205 — Audio 5, Audio 10 CD, Audio 20, COMAND NTG 1/4/4.5/5
• E-Klasse W210 / W211 / W212 / W213 — Audio 50, Audio 20, NTG 2/4.5
• A-Klasse W168 / W169 / W176 / W177 and B-Klasse W245 / W246
• GLC X253, CLA C117, and other current models using Audio 20/COMAND NTG5

BMW

BMW used Becker units for its Business and Navigation CD systems before switching fully to Harman/iDrive platforms. Affected models include E46, E60, E90, and early E-series using the Becker 2000 and Navigation units (GR serial).

Audi

Audi Concert, Symphony and early Navigation units on A3 8L/8P, A4 B5/B6/B7 were manufactured by Blaupunkt/Becker or Philips/Becker (AUZ serial).

Porsche

Classic Porsche 911 (996/997), Boxster (986/987), and Cayenne I (9PA) fitted Becker CDR 2005, CDR 2006, and PCM units with BE serials.

See all supported models at radiocodelookup.com/brands.

Serial Number Format — The BE Serial

Becker OEM units use a serial beginning with the two-letter prefix BE followed by a sequence of digits or alphanumeric characters. On Mercedes units this is consistently printed on a sticker on the unit casing. On BMW units the GR serial format is used instead of BE.

• Mercedes: BE serial on casing label, e.g. BE1234567
• BMW Business CD: GR serial on casing label, e.g. GR1234567
• Audi (Becker-origin): AUZ serial on casing, 14 characters
• Porsche CDR/PCM: BE serial on casing, sometimes combined with part number

How to Find the Serial Number

1. Mercedes Audio 10/20 — physical label: The radio can be removed by pressing the four sprung-wire clips on the front panel (a flat-blade tool or DIN keys release them). The BE serial sticker is on the top of the unit.
2. Mercedes COMAND / Audio 20 — on-screen: On COMAND NTG 4/5 units navigate to Vehicle → Settings → System to find the serial number displayed.
3. BMW: Use DIN extraction keys to remove the head unit. The GR serial is on the top casing sticker.
4. Porsche CDR: Remove the radio from the centre console (two screws plus DIN cage). The BE serial is on the side sticker.

How to Enter the Code

• Mercedes Audio 10 CD / Audio 20 (button units): Press preset buttons 1–4 to set each digit, then press and hold a confirmation button (varies by model — typically the AM/FM or seek button) to confirm the five-digit code.
• Mercedes COMAND NTG (controller units): The COMAND controller (iDrive-style knob) navigates the code entry screen. Rotate to change digit, push to confirm each, and navigate to the OK button for final confirmation.
• BMW Business CD (GR serial): Preset buttons 1–4 to cycle digits; the seek button to confirm.
• Porsche CDR 2005/2006: Same preset button method as Mercedes button units.

Vehicle / Class	Radio Model	Serial Format	Code Length
Mercedes W203 / W204	Audio 5, Audio 20	BE prefix	5 digits
Mercedes W212 / W213	Audio 20 / NTG4.5	BE prefix	5 digits
BMW E46 / E60 / E90	Business CD, Becker 2000	GR prefix	5 digits
Audi A3 8P / A4 B6/B7	Concert, Symphony	AUZ (14 chars)	4 digits
Porsche 911 996/997 / Boxster	CDR 2005/2006	BE prefix	5 digits

Troubleshooting

• Mercedes Audio shows no code prompt after power-up: Becker units on Mercedes typically show the code prompt immediately on power-up, not after the SAFE message. If the display is blank, ensure the ignition is fully on (position II) and the unit has power.
• BMW shows SAFE but not a digit prompt: Older BMW Business CD units cycle from SAFE to a four-dash prompt after a brief pause. Wait 10–15 seconds after the SAFE display before entering the code.
• COMAND vehicle-bound units: High-spec COMAND units in some Mercedes models (particularly those with integral navigation hardware) are VIN-bound and do not use a code — they require dealer reactivation via diagnostic tools. If pressing buttons on the COMAND screen shows no code prompt after a battery change, this may be the case.

Frequently Asked Questions

Is Becker now part of Harman?

Yes. Becker was acquired by Harman International in 2005. Later Mercedes and BMW radios carry Harman branding or the Harman Kardon premium audio label. For code purposes, units manufactured under the Becker name use BE/GR serials, while newer Harman-built units are described separately.

My Mercedes C-Klasse W204 shows a five-digit code entry — is that normal?

Yes. Becker OEM units for Mercedes use a five-digit unlock code, unlike the four-digit codes common in VW or Ford radios. Ensure you retrieve a five-digit code when looking up a BE serial.

Where is the BE serial on a Mercedes A-Klasse W176?

The W176 uses the Audio 20 CD NTG4.5 or COMAND NTG5 system. For Audio 20, remove the unit using the DIN clip release method and read the BE sticker. For COMAND NTG5, the serial is in the Vehicle → Settings → System menu.

Can I unlock a Porsche CDR 2006 myself?

Yes. The Porsche CDR 2005 and CDR 2006 use standard BE serial-based codes and the standard preset-button entry method. Remove the unit from the centre console to read the BE serial, then look up your code at radiocodelookup.com/brands.

My BMW iDrive says it needs a code — is that a Becker unit?

BMW iDrive systems (CCC, CIC, NBT, NBT EVO) are Harman-built, not Becker. They are vehicle-bound and do not use a removable code card — reactivation requires BMW dealer tools. Only the older Business CD and Navigation CD units (E-series BMWs pre-2004) use GR serials and standalone codes.