U0185 – Lost Communication With TV/Telematics Unit means the vehicle’s BCM, PCM, cluster, or infotainment system can no longer communicate with the telematics/TV module over the CAN network. This module handles connected services such as navigation, emergency call systems, live traffic data, subscription features, remote diagnostics, and sometimes TV playback in certain markets. When communication is lost, features may stop working, warnings can appear, and other modules may log additional network faults. This guide explains what U0185 means, symptoms, causes, diagnostics, and the best repairs.
What Does U0185 Mean?
U0185 is a generic network communication DTC that appears when the telematics or TV module stops responding on the CAN bus. The telematics unit typically manages SOS calls, remote vehicle tracking, GPS data, cellular connectivity, and OTA service features. In some regions, it also includes TV receiver functions.
If this module fails or drops offline, the vehicle may lose access to navigation updates, emergency call features, or infotainment data. While drivability is usually unaffected, certain safety or connected-service functions may be unavailable until communication is restored.
Quick Reference
- OBD-II Family: U-Code (Communication Network)
- Scope: Generic
- System: Telematics / Infotainment / CAN Bus
- Difficulty Level: Easy to Moderate
- Estimated Repair Cost: €50–€700+
- Last Updated: 22 November 2025
Real-World Example / Field Notes
A crossover SUV came in with navigation stuck on “Loading…” and the emergency call indicator illuminated on the dashboard. The PCM and BCM logged U0185. The root cause was a failed antenna amplifier that caused the telematics module to repeatedly reboot and drop off the CAN bus. Replacing the amplifier restored system stability.
Another case involved a luxury European sedan where live traffic, voice control, and online services suddenly stopped working. U0185 was stored across multiple modules. Water intrusion from a blocked sunroof drain had corroded the telematics module located in the trunk side compartment. Cleaning the corrosion and resealing the drains solved the issue.
Symptoms of U0185 – Lost Communication With TV/Telematics Unit
- No navigation / GPS services: Map functions may freeze or fail to load.
- Emergency call malfunction warning: “SOS system unavailable.”
- Live traffic / connected services offline: No data reception.
- Blank or frozen telematics screen: Module stuck in reboot cycle.
- Vehicle settings missing: Some cars store settings in the telematics unit.
- No communication with module via scan tool: Unit unresponsive.
- Bluetooth/voice control failures: Depending on integration.
Common Causes of U0185
Most Common Causes
- Loss of power or ground at the telematics module
- Corroded connectors (very common in trunk-mounted units)
- CAN bus wiring issues: shorts, opens, or water intrusion
- Internal failure of the telematics/TV unit
- Low battery voltage causing module resets
Less Common Causes
- Antenna amplifier or GPS receiver faults causing module lockup
- Rodent damage in roof or trunk wiring paths
- Incorrect aftermarket installations (dash cams, trackers, stereos)
- Failed CAN terminating resistor drawing network low
- Software corruption after an interrupted OTA update
Diagnosis: Step-By-Step Guide
Diagnosing U0185 requires checking power, grounds, connector integrity, and CAN signal stability at the telematics/TV unit.
Tools You’ll Need
Advanced scan tool, trim removal tools, multimeter, wiring diagrams, backprobe pins, CAN breakout box, and optional oscilloscope.
- Scan all modules: Confirm U0185 is present and check for other communication codes.
- Locate the telematics unit: Often in the trunk, roof console, rear quarter panel, or under the dash.
- Check power and ground: Ensure correct battery voltage and clean grounding points.
- Inspect connectors: Look for corrosion, moisture, damaged pins, or loose plugs.
- Measure CAN-H and CAN-L voltage: Expect ~3.5V (H) and ~1.5V (L). Deviations indicate wiring faults.
- Check for water intrusion: Especially behind trunk liners or roof areas.
- Continuity test CAN lines: Check for opens between the telematics unit and BCM.
- Disconnect aftermarket equipment: Devices tied into CAN can disrupt communication.
- Hard reset the module: Remove fuse or disconnect battery briefly to reboot the system.
- Oscilloscope CAN test: Look for noise or a stuck module flattening the waveform.
Pro Tip: Many telematics modules are mounted in moisture-prone areas. Even minor condensation can cause intermittent U0185 faults long before the module completely fails.
Possible Fixes & Repair Costs
- Repair or clean corroded connectors: €20–€80
- Repair CAN wiring in trunk or roof area: €60–€200
- Fix water leaks (sunroof drains, trunk seals): €50–€250
- Replace telematics/TV unit: €200–€700+
- Replace GPS antenna/amplifier: €50–€150
- Charging system repair (if voltage-related): €120–€400
Can I Still Drive With U0185?
Yes. U0185 does not affect engine or transmission operation. However, you may lose access to emergency call features, navigation, live traffic updates, or connected services. In some regions, the SOS system is part of legal vehicle safety requirements, so the fault should be repaired promptly.
Related Codes
- U0151 – Instrument Panel Communication Fault
- U0141 – Steering System Network Communication Fault
- U0121 – Lost Communication With Anti-Lock Brake System (ABS) Control Module
- U0102 – Lost Communication With Transfer Case Control Module
- U0101 – Lost Communication With TCM
- U0100 – Lost Communication With ECM/PCM "A"
- U0195 – Lost Communication With Audio AMP
- U0194 – Lost Communication With Audio Display
- U0188 – Lost Communication With Video Display
- U0184 – Lost Communication With Radio
Key Takeaways
- U0185 means the telematics/TV module has stopped communicating over CAN.
- Common causes include corrosion, wiring damage, moisture, or low voltage.
- Navigation, SOS, or connected services may stop working.
- Most repairs are simple unless the module itself has failed.
FAQ
Does U0185 mean the telematics module is dead?
Not always. Most faults involve power, ground, or connector issues rather than full module failure.
Can water intrusion cause U0185?
Yes. Telematics modules in trunks or roof areas are especially prone to moisture problems.
Will U0185 affect navigation?
Yes. Many navigation systems rely on the telematics module for GPS data or online updates.
Is it safe to drive with U0185?
Yes, but emergency call features and connected services may be unavailable.
Can aftermarket electronics cause U0185?
Very often. Incorrect splicing into CAN wiring for dash cams, alarms, or trackers can cause communication faults.