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Service bulletin LI82.85-P-079530

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11020699
Published by NHTSA2025-07-15
Manufacturer's numberLI82.85-P-079530
Manufacturer's date2025-07-12
NHTSA componentELECTRICAL SYSTEM

NHTSA's summary

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 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 Device and Software Topics: Head Unit Software/Hardware: • Hardware causes or outdated firmware in the vehicle’s head unit can prevent a stable connection. iPhone Software/Hardware: • Similar causes in the iPhone, including outdated iOS versions or hardware causes, may affect performance.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: • Cables: A compromised or poor-quality iPhone-USB cable can cause intermittent or total loss of connection. • USB Ports: Dust, debris, or physical deformation 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: • 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 Please see attachment for further details

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system

Vehicles listed
MERCEDES-BENZ AMG C432023 to 2024
MERCEDES-BENZ AMG C63 S E2024
MERCEDES-BENZ AMG GLC432024
MERCEDES-BENZ AMG GLC63 S E2025
MERCEDES-BENZ C 3002022 to 2025
MERCEDES-BENZ E 3502025
MERCEDES-BENZ E 350 4MATIC2025
MERCEDES-BENZ E 450 4MATIC2025
MERCEDES-BENZ E 450 4MATIC ALL-TERRAIN2025
MERCEDES-BENZ GLC 3002023 to 2025
MERCEDES-BENZ GLC 300 4MATIC2023 to 2025
MERCEDES-BENZ GLE 450 4MATIC2025
MERCEDES-BENZ GLE 450 4MATIC COUPE2025

Listing a model year does not mean every vehicle of it is concerned: the document says which.