A Mercedes radio code is tied to the head unit serial on the casing label, usually a long string starting with the unit part number and ending in a serial group. Enter the serial on this page and the code is retrieved for £19.99, refunded in full if no working code can be supplied.
Radio codes belong to the head unit serial number, not the vehicle registration or VIN.
A flat battery, battery replacement or radio removal is what triggers the code prompt.
Mercedes-Benz serial formats: Becker Audio 10 / Audio 30 (e.g. BE1234); Alpine / Sound 5 (e.g. AL1234567); Audio 20 / COMAND (e.g. A1234567890).
Display messages: CODE = The four-digit security code is required. · WAIT / SAFE = Timed lockout after failed attempts — keep the ignition on. · ERR = Incorrect code entered.
Bob's never displays a guessed or generated code — if a working code can't be retrieved you get a full refund.
Where to find the serial number, what the display messages mean and how to key the code back in on a Mercedes-Benz.
The Mercedes radio code is a four-digit anti-theft code stored against the head unit serial. It is separate from the vehicle's own electronics, so a radio moved from one Sprinter to another arrives locked.
When you'll be asked for the code:
After a flat battery — very common on Sprinters and Vitos left standing
After a battery replacement or terminal disconnection
When a used Audio 10 or Sound 5 unit is fitted
Following auxiliary battery failure on vans and campers
Serial number formats:
Becker Audio 10 / Audio 30 — for example BE1234. C-Class, E-Class, Sprinter — BE prefix on the casing label.
Alpine / Sound 5 — for example AL1234567. A-Class, Vito and later Sprinter units.
Audio 20 / COMAND — for example A1234567890. Later systems, often vehicle-coded rather than four-digit locked.
How to find the serial number:
Check the handbook wallet — Mercedes supplied a code card with most vans and cars.
Mercedes units very rarely display the serial, so the unit comes out on a pair of U-shaped extraction keys.
Push the keys into the slots either side of the fascia until they click, then draw the unit out squarely.
Read the label on the top or side of the casing, noting the BE or AL prefix in full.
Disconnect the battery before pulling the unit on airbag-equipped dashes.
What the display messages mean:
CODE — The four-digit security code is required.
WAIT / SAFE — Timed lockout after failed attempts — keep the ignition on.
ERR — Incorrect code entered.
How to key the code in:
Use the preset buttons 1 to 4 to set each digit on Becker units.
On Sound 5 units the arrow keys set the value and the OK button advances.
Confirm with a long press on the last preset or the OK button.
The unit returns to normal play once accepted.
Audio 10, Audio 20 and the Becker units
The coded units are the Becker and Alpine-built Audio 10, Audio 20, Audio 30 APS and the Sound 5000 and 4000 radios found in the C-Class W203, E-Class W211, A-Class W168 and W169, Vito and Sprinter. The display shows a row of dashes or asks for the code after the battery has been off.
COMAND NTG systems and the later MBUX screens are vehicle-coded rather than audio-coded. If you have a fixed tablet-style screen on the dash top, a flat battery will not lock it behind a four-digit code.
Removal on a Mercedes
Most of these units come out on two pairs of flat or hooked release keys pushed into the slots at each corner of the fascia. Becker units in particular need the keys fully home before any pull — a partial insertion feels like it has engaged and then bends the catch.
On a Sprinter and Vito the radio aperture is usually surrounded by hard, sun-aged plastic and often has aftermarket wiring behind it from a previous tracker or DAB install. Take the surround off first and check what is behind before pulling anything through.
The label carries several numbers. You want the serial group, not the ten-digit part number — photograph the whole label and let us pick out the right one.
Cost and lockouts
£19.99 here against the serial, with a full refund if no working code can be supplied. A Mercedes dealer is usually the dearest of the lot at around £30 to £50 for a lookup, plus workshop time to remove the unit.
Becker units count failed attempts and then impose a long wait — sometimes an hour or more. Leave the ignition on so the timer runs, and if the battery is marginal put a charger on it, because a Sprinter sitting in position II for an hour with a tired battery will not thank you.
Where is the Mercedes radio code card? Usually in the handbook wallet or the service book. On ex-fleet Sprinters and Vitos it is often missing, which is when the serial route is needed.
My Sprinter radio says WAIT The unit is in a lockout after failed attempts. Leave the ignition on so the countdown runs. Turning the key off restarts the timer.
Does COMAND need a radio code? Generally no. COMAND and Audio 20 systems are coded to the vehicle rather than protected with a classic four-digit audio code, which is a dealer-level job if disturbed.
Can I get the code from the VIN? Only the factory-fitted unit relates to the VIN. If the radio has been changed — extremely common on working vans — the VIN answer would be wrong.
How much is a Mercedes radio code? £19.99 on this page against the head unit serial, with a full refund if no working code can be supplied.
Where is the serial on a Mercedes radio? On the label on the top or side of the unit casing. Photograph the whole label — the serial group matters, not the longer part number printed alongside it.