Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
RNS 315+
Familiarity with the function and operation is needed if there are customer concerns.
The RNS 315+ radio/navigation system has the following:
- Display: 5-inch color display
- Integrated CD player
- SD Memory Card Reader
- UHV Low/Premium
- Navigation function using a 3D card and language
- CD/SD Navigation (Navigation without a CD inserted)
- 4 speaker channels, 20 W each
- Multimedia System Control Module -J650- connection
- Connection for External Audio Source Connection -R199-
- Connection for an external CD Changer -R41-
- Connection for an external sound amplifier (Amplifier -R12-)
- USB Connection
- OPS (Optical Parking System)
- A/C information shown in the radio display
- Optional support for the multifunction steering wheel
- Comfort coding
- An optional universal cellular telephone preparation (UHV) with an integrated Bluetooth antenna
It is not possible to play the following CD formats:
- 8 cm CDs
- "Mix CDs" (CDs containing files and audio files)
The RNS 315+ is equipped with OBD.
For troubleshooting, use the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
Repairing Antenna Wires
General Information, refer to General Information .
Electronic Anti-Theft Protection
The RNS is equipped with convenience anti-theft protection, which operates in conjunction with the instrument cluster. The radio code is stored internally inside the RNS and inside the instrument cluster.
After disconnecting the power supply to the RNS, it is ready for use and the radio code does not need to be entered again. The requirement is that the first activation of the electronic anti-theft system follows and that the RNS (Radio Navigation System) is reconnected in the same vehicle.
Use the Vehicle Diagnostic Tester to get the radio code. The radio card and the label on the RNS (Radio Navigation System) that were used in the past are no longer used.
The Vehicle Diagnostic Tester must be "online" to retrieve the radio code and the user must be authorized to access radio codes.
Reactivating a locked RNS (Radio Navigation System) is only possible by entering correct number code for anti-theft protection.
Determine the radio code using Vehicle Diagnostic Tester:
-- Connect the Vehicle Diagnostic Tester.
-- Select Guided Fault Finding .
-- Use the GO TO button to select the "function/component selection" and the following menu options one after the other:
- Body
- Electrical Equipment
- 01 - On Board Diagnostic (OBD) capable systems
- Radio/navigation system
- Radio/navigation system functions
- Radio code inquiry
Authorization will be requested from the system: Then the operating data, the VIN and the radio serial number of the radio/navigation system will be automatically read out.
It is possible that the Vehicle Diagnostic Tester will not be able to read the serial number when a new RNS is installed. In this case enter the unit number manually. The serial number can be found on a sticker on the unit and is also stamped into the side of the RNS (Radio Navigation System).
The Vehicle Diagnostic Tester will display the anti-theft code.
Manually enter the radio code in the RNS (Radio Navigation System).
Electronic Anti-Theft Protection, Deactivating:
-- Turn on the RNS.
"SAFE" appears in the display for approximately 10 seconds, after that "1000" appears.
-- Enter the correct radio code using the buttons on the radio.
-- Press the input screen to confirm in the entry.
The RNS (Radio Navigation System) is enabled and ready for operation.
Use the correction screen to erase an incorrect code.
It is possible to enter the radio code again if it was entered incorrectly. If radio code is entered incorrectly twice, then the RNS (Radio Navigation System) is locked for an hour. Leave the RNS and ignition on. The process can be repeated again after an hour. Note: Always two attempts, after that the RNS (Radio Navigation System) will lock up for one hour.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.