This article will explain what is a Mercedes Benz E320 radio code? And answer the following question: When will you need the radio code? What are the retrieval methods for radio code in Mercedes Benz E320?

What is the 1999 Mercedes E 320 radio code?

In the 1999 Mercedes Benz E320, radio code is used for activation of the radio or cockpit management and data system command for short. It is assigned to the radio control unit and activated at the time of production of the vehicle.

To reduce the number of theft of audio and radio systems in the Mercedes Benz vehicle, the company started using the radio code as an anti-theft measure. If for some reason the radio innit in the vehicle needed replacement, the dealership used to provide a replacement code along with the new radio control unit. 

The Mercedes Benz E class has always been the highest selling and very reliable, the 1999 model of E class was a facelift version of the second generation in the E class. The Second Generation of the E class was launched in 1995 with the model series W210, it featured an updated design to appeal to a wider customer age group and also had many mechanical improvements like rack and pinion steering rack, double-wishbone suspension and on some models SBC Sensotronic brake system.

The 1999 E320 used the Command 2.0 control unit; it acted as the common control unit for all additional telematics functions like GPS navigation. The central command unit is connected to different devices like CD/ DVD changer, mobile cradle, sound system amplifier.

 The number of additional devices depended upon the equipment list of the vehicle. All the devices communicated over the D2b optical network which was later replaced by much faster optical fibre MOST connections.

Few 199 E 320 models shipped with inbuilt cassette drive, the command control unit or the radio unit were manufactured by companies like Harman Becker and Mitsubishi. It had an internal memory keep function to store radio stations, customer settings and more vitally the radio code. 

The memory keeps alive function uses a small battery or capacitor which starts discharging if the power supply to the control module is interrupted. All the data stored in the memory is lost if these internal capacitors or batteries were to discharge completely.

When will you need the codes?

As the codes are stored on the internal memory of the radio control unit, the control unit will ask for code in the following circumstances:

• The main battery is dead.

If the main battery is under 4 volts or completely dead, the internal capacitors are discharged completely. Data stored in the memory is lost. After replacing the main battery, there is no code stored in the control unit to verify if the control unit is still installed in the original vehicle or it is installed in another vehicle. Even if the vehicle is jump-started a few hours after the battery is dead, the control will still need the radio code for resuming operation.

• Replacing the radio control unit

If the original control unit must be replaced in a vehicle then the new control unit will need a radio code before bringing it back into operation. This process is also known as an initial startup of the control unit. As the 1999 E class had OBD 2 port, a diagnostic tool can be connected and the new radio control unit is personalised into the vehicle.

• Installing the used radio control unit.

When a working used radio unit is installed in another vehicle to diagnose the fault in the audio system of the vehicle, then the code is requested after the installation of the radio is completed in the affected vehicle. The radio code is again requested when the radio control unit is removed from the affected vehicle and installed in its original vehicle.

What are the methods to retrieve radio code in Mercedes Benz e320?

When the ignition is turned on or the vehicle is started and CODE appears on the display of the radio, it is a sign that the radio control unit has been reset and will need the radio code before resuming its function.

The followings are the methods that can be used to retrieve the radio codes:

• Vehicle owner’s manual

In 1999, the E320 was usually shipped with an owner’s manual or provided to the customer at the time of delivery. The owner’s manual contains all the information necessary for the correct operation of the vehicle. The radio code is also printed in the owner’s manual or usually returned on a card. Depending on the original parts manufacturer of the radio control unit, the code can be from 4 to 6 digits.

• VIN.

The VIN is a 17 digit vehicle identification number, for the E 320 it usually started with the letters ‘WDB210XXX XXX XXX’. VIN is located on the vehicle near the B pillar and under the driver or front passenger seat. It contains all the information regarding the vehicle such as what kind of engine, left or right-hand side steering and most importantly the vehicle equipment lists or the SA codes.

Any authorised Mercedes Benz workshop can retrieve the radio code by checking the vehicle identification number against the central vehicle database. The only proof of vehicle ownership is required to get the code from the workshop.

• Visit an Authorised workshop.

Mercedes Benz has proprietary diagnosis software, in the 1999 E 320, it was known as DAS. The technician can connect the vehicle interface unit and perform an initial startup of the command/radio control unit. No actual code is required in this method as the control unit accepts the initial startup request from the diagnosis tool and verifies the code in the central vehicle database.

How to enter the Mercedes Benz radio code in 1999 E320?

Depending on the type of radio control unit present on the vehicle, there will either be a knob with volume and power buttons integrated into it or a 1-9 number switcher to save the radio stations.

Following is the process to enter the radio codes:

• Turn on the ignition in the first position and press the power button on the radio.
• Check if the letters CODE appears on the radio display, this confirms that the radio has lost the code.
• For models with volume control/power knob. Turn the knob unit letter 1 appears in the place of the first digit and rotate it until the correct number comes on the display, press the knob once to confirm the entry.
• Repeat the process until the complete code is entered, the radio should be operational after entering the last digit.
• For Models with individual number switches, the process is very straightforward, simply enter the correct number by pressing the respective number switch.
• In case there was any mistake while entering the code then, simply turn off the ignition and start once again.

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Conclusion

The radio code is the most effective way to prevent theft or reselling of used radio control units in the market. Mercedes Benz still uses anti-theft protection on the command/ radio control unit in the latest vehicles.

References 

• https://en.wikipedia.org/wiki/Harman_Becker_Automotive_Systems

FAQs: What is the 1999 Mercedes E 320 radio code

How do I find my Mercedes radio code?

The Mercedes Benz radio code is written in the owners’ manual. If the owners’ manual is lost then contact the authorised dealership for the radio code.

How do I get the radio code for my Mercedes e320?

The radio core of the E320 is written in the owner’s manual. There is a serial number written on the back of the Mercedes Benz Radio unit, authorised dealerships can find out the correct radio code for the respective serial number.

How do I unlock my car radio without the code?

It is not possible to unlock the car radio without the radio code, radio code is a type of anti-theft measure and prevents theft of car radios.