Removing and installing radio - ra820d1407502x(7502)

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D. Coding MB radio, radio and navigation control module (5-digit fixed code) Model 140

D. Coding MB radio, radio and navigation control module (5-digit fixed code)

When the radio is disconnected from the power supply it does not function when reconnected. The word "CODE" appears on the display after the ignition and radio are switched on.
The code number for the radio is indicated on the enclosed CODE CARD.
Enter the code number with the station buttons, e.g. digit 1 with station button 1.
NOTE: After entering the first digit the word "CODE" disappears and the number entered is displayed followed by 4 dashes. The next digit to be entered flashes. After entering all 5 numbers, the first digit starts flashing again. The code number can be written over as frequently as desired in this state. Correction can only be made by reentering the complete number.
Confirm code number:
On MB radio press TUNE, AUTO/SEEK or SC button. On radio and navigation control module (APS) press enter key. The unit automatically switches on and indicates the radio station or frequency stored with station key 1.
If the wrong code number is entered and confirmed, the word "CODE" appears again on the display. If the wrong code is entered three times the word "WAIT" appears on the display and entry is inhibited for approx. 10 minutes. Three further incorrect entries inhibit the unit for 10 minutes again. Three more incorrect entries (total of 9 incorrect entries) increase the inhibit time to 60 minutes. Another three incorrect entries inhibit the unit for 60 minutes again.
The waiting period expires only when the radio is switched on.