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.
Overview - Microphone Unit
The Microphone Unit In Front Roof Module -R164- is installed in the Front Interior Lamp -W1-. Up to three microphones may be installed, depending on the equipment.
One microphone (Interior Microphone -R74-) is connected directly to the Digital Sound System Control Module -J525-. The other microphone (Telephone Microphone -R38-) is connected to the Information Electronics Control Module 1 -J794-.
For NZ3, the Telephone Microphone -R38- is connected to the Control Module for Emergency Call Module and Communication Unit -J949- and is >>looped through<< to the Information Electronics Control Module 1 -J794-.
The Microphone Unit in Front Roof Module -R164- located in the Front Interior Lamp -W1- can be replaced only as a complete unit. It is not possible to replace individual microphones (Interior Microphone -R74- or Telephone Microphone -R38-).
Microphone Unit In Front Roof ModuleR164, 3- and 5-Door Vehicles and Sedan
- Front Interior Lamp -W1-
- 4-Pin Connector -T4t-
- Interior Microphone -R74-, Black to the Digital Sound System Control Module -J525-
- Telephone Microphone -R38-, gray, for NZ0 to the Steuergerαt fμr Informationselektronik 1 -J794- ; for NZ3 to the Control Module for Emergency Call Module and Communication Unit -J949-
Microphone Unit In Front Roof ModuleR164, Convertible
- 4-Pin Connector -T4t-
- Telephone Microphone -R38-, gray to the Information Electronics Control Module 1 -J794-, MMI
- Interior Microphone -R74-, Black to the Digital Sound System Control Module -J525-
Connector Assignment
1 - 4-Pin Connector -T4t-
- Microphone 1, Telephone Microphone -R38- to the Information Electronics Control Module 1 -J794-
- Microphone 1, Telephone Microphone -R38- to the Information Electronics Control Module 1 -J794-
- Microphone 2, Interior Microphone -R74- to the Digital Sound System Control Module -J525-
- Microphone 2, Interior Microphone -R74- to the Digital Sound System Control Module -J525-
2 - Microphone 1, Telephone Microphone -R38-
3 - Microphone 2, Interior Microphone -R74-
Microphone Unit in Front Roof Module -R164-, removing and installing. Refer to Microphone Unit in Front Roof Module -R164-, REMOVING AND INSTALLING .
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.