Proper Application Of Chip Protection Films (VERSION 1)

WARNING: This page is about the GLC300 4Matic, 4D Utility, which is a different variant/trim than selected.

Publication date: 2024-09-09
Reference number: VERSION 1
Supersedes refnos: LI98.00-P-078106

ALL MODEL SERIES WITH MBUX NTG7 - CONNECTIVITY INTERRUPTIONS FOR APPLE CARPLAY

TECHNICAL SERVICE BULLETIN

Reference Number(s): LI82.85-P-079088 Version 1, Date of Issue: May 30, 2025

MERCEDES-BENZ:	All model series with NTG7
FUNCTION GROUP:	82.85 - Navigation and Communication systems

COMPLAINT

The following most common complaints may be observed:

Brief connectivity interruptions when using Apple CarPlay over Wi-Fi
Audio cuts out
Device not recognized
No operation possible

CAUSE

There are multiple possible causes for an iPhone disconnecting from a vehicle's head unit while using Apple CarPlay.

These include hardware, software, and environmental factors:

ENVIRONMENTAL INTERFERENCE

External Sources:

Passing under toll bridges, driving near airports, or areas with heavy electronic interference (e.g., as described in LI82.85-P-076157 MBUX NTG7 - CONNECTIVITY INTERRUPTIONS FOR APPLE CARPLAY OVER WI-FI ) can cause connection drops.

Cellular Networks:

Interference from nearby cell towers operating on similar frequencies (usually 2.4GHz or 5GHz) can disrupt the signal.

Storage Location:

Keeping your phone in a handbag or surrounded by other objects inside the vehicle can create physical or electronic interference.

DEVICE AND SOFTWARE ISSUES

Head Unit Software/Hardware:

Outdated firmware, bugs, or hardware faults in the vehicle's head unit can prevent a stable connection.

iPhone Software/Hardware:

Similar issues in the iPhone, including buggy iOS updates or hardware problems, may affect performance.

Reset or Reboot:

Automatic rebooting or resetting of either the head unit or the iPhone will temporarily disrupt CarPlay.

CONNECTION AND SETTINGS

Wired Connections:

Faulty Cable: A damaged or poor-quality USB cable can cause intermittent or total loss of connection.
USB Port Issues: Dust, debris, or physical damage in the USB port of either the head unit or the iPhone can also lead to disconnects.

Wireless Connections:

Intermittent Bluetooth/Wi-Fi: Unstable wireless communication (Bluetooth/Wi-Fi) can frequently break the Car-Play connection.

Power Management:

Battery Saver Mode: Enabling low power mode may restrict background processes, affecting CarPlay.
Vehicle's Electrical System: Unstable power delivery from the car's battery or electrical interruptions can cause the head unit to malfunction.

PHONE & APP CONFIGURATION

Phone Settings:

Incorrect or conflicting settings (especially Bluetooth or Wi-Fi) on your iPhone can interfere with the CarPlay link.
Third-Party Apps/Profiles:
Installed apps or configuration profiles may conflict with CarPlay's operation.
Native apps are apple maps, apple music, audio books, apple news, podcasts, messages and phone. All other apps are considered third party apps.

App Conflicts:

Running conflicting apps that require similar system resources as CarPlay can cause instability.

Mobile Data Plan:

Streaming from online sources without sufficient mobile data can result in lost connectivity.

OTHER FACTORS

Heat & Overheating:

If either the phone or the head unit overheats, they may disable certain functions to prevent damage, leading to disconnection.

User Actions:

Accidentally disconnecting the device in settings, or physically moving or bumping the phone or cable, may disrupt the connection.

REMEDY

Guided Diagnostic Path for Apple CarPlay Connection Issues

Please follow the steps below to systematically diagnose and resolve CarPlay concerns:

Update Devices:

Ensure the iPhone is updated to the latest available iOS version.
Ensure the vehicle's head unit is updated to the latest software version available.

Isolate the Issue:

Check whether the symptom persists with another iPhone running the latest iOS version.
Test both wireless and wired CarPlay connections:
Does the issue only occur with wireless CarPlay?

Does the wired connection to the phone function correctly?

Further Troubleshooting Steps:

Reboot the iPhone.
Reboot the head unit via the settings menu (user data reset).
Remove saved CarPlay connections
Delete the head unit information from the iPhone (see attached video for guidance).
Delete the iPhone from the head unit's list of paired devices.
Remove the head unit entry from CarPlay settings on the iPhone.
Re-initiate pairing between the head unit and the iPhone to establish a new connection certificate.

Documentation and Additional Testing:

If possible, provide a picture or short video showing the symptom.
Check if similar symptoms occur when using Android Auto (if available)

Open a tips case with the attached questionnaire fully completed. A request for head unit logging may be needed. If determined the head unit logs are needed to further diagnose the symptom the instructions to do so will be provided in the TIPS case.

NOTE: Obtain Customer Consent (if requested in the TIPS case): If the head unit log review may be needed, have the customer sign the data consent form so head unit logs can be analyzed for root cause (reference LI82.85-P-077316 MODEL SERIES 214 AND 236: POTENTIAL CONCERNS WITH CIVIC A26/17 - MBUX MULTIMEDIA SYSTEM + INSTRUMENT CLUSTER (HEAD UNIT)] AND/OR DISPLAYS to obtain the consent form).

ATTACHMENTS

File	Description
Deleting carplay from iPhone.MP4	Removing Apple CarPlay connection from the iPhone
ACP Questionnaire.pdf	Please complete this questionnaire

Disclaimer

NOTE: The information contained in this document is intended for use by trained, professional technicians with the knowledge to properly and safely perform diagnosis and repairs on Mercedes-Benz vehicles, using Mercedes-Benz approved tools and equipment. It informs service technicians about conditions that could occur in certain vehicles and provides information that could assist in proper vehicle diagnosis, service, or repair. It does not indicate that a defect is present in any vehicle referenced in this document nor does it imply warranty coverage. DO NOT assume that a symptom or condition, or a described cause of a symptom or condition, affects any particular vehicle or groups of vehicles, or that a described repair applies to any particular vehicle or groups of vehicles. There can be multiple causes resulting in the same or similar symptoms or conditions described in this document, and trained professional service technicians must use their diagnostic skills to make evaluations on a case-by-case basis. The information contained in this document does not guarantee warranty coverage nor does it extend the vehicle's warranty in any way.

SYMPTOMS

Communication/information > Entertainment > USB input > Malfunction

Communication/information > Entertainment > Apple CarPlay > Malfunction

Communication/information > Entertainment > Apple CarPlay > No connection possible

OPERATION NUMBERS/DAMAGE CODES

Op. no.	Operation text	Time	Damage code	Note
		0.000 H	820D2	Use the following when submitting the warranty claim. Ensure you are using the correct fault location.