Code
U1444
HYUNDAI
U — Network/User
Mozen : Ring Break Between Mozen Unit and Head Unit, Non Mozen : Ignore
Views:
UK: 24
EN: 27
RU: 40
AI status
Completed
Completed
100%
Causes
- Open or damaged wiring in the communication ring between Mozen unit and head unit
- Corroded, loose or pushed-out connector pins at either module or intermediate splice
- Failed Mozen unit or head unit communication interface
- Poor ground or power supply to one of the modules
- Water intrusion or physical damage to harness/connector
- Software mismatch or module not configured for vehicle (module not present or disabled)
Symptoms
- Loss or intermittent operation of infotainment/navigation features tied to the Mozen unit
- Warning or message on cluster or head unit about communication error
- No audio, limited touchscreen functions, or features disabled
- Erratic or intermittent system behavior related to the affected modules
What to check
- Confirm vehicle application: verify if the vehicle is fitted with the Mozen unit. If not fitted, code can be ignored.
- Read all U-codes and module data with a manufacturer-level scan tool; capture freeze frame and recent data
- Visual inspection of wiring and connectors between head unit and Mozen unit for damage, corrosion or water ingress
- Inspect and reseat connectors at both modules and any intermediate junctions or splices
- Check module power and ground circuits for proper voltage and resistance
- Measure bus continuity and termination resistance between the two modules (expected ~60 ohms across CAN H-L with both terminators present)
Signal parameters
- Bus idle voltages (typical CAN): CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V; dominant state shifts CAN_H higher and CAN_L lower
- Voltage difference when dominant: typically ~1.5–2.0 V differential (varies by vehicle/protocol)
- Termination resistance: about 60 Ω across H-L with both 120 Ω terminators in place
- Expected message traffic: regular message IDs from both head unit and Mozen unit (use factory tool to view IDs and frequency)
- Continuity of ring conductor (low ohms between modules when disconnected from modules)
Diagnostic algorithm
- Verify vehicle configuration and confirm Mozen unit is installed and supported. If not installed, document and ignore code.
- Use factory scan tool to read U1444 details, freeze frame, and related module fault codes. Note any other communications codes.
- Perform visual inspection: check harness routing, grommets, connectors, and signs of chafing, corrosion or water intrusion between the head unit and Mozen unit.
- With ignition OFF, disconnect both modules and measure continuity of the ring conductor(s) through the harness and any intermediate connectors/splices. Repair any open circuits.
- Measure resistance across CAN H-L at the two module connectors (key off). Expect roughly 60 Ω if both terminators present. Investigate abnormal values.
- With key ON (engine off), check module supply voltage and ground at each module. Repair any power/ground faults.
- Reconnect modules and use an oscilloscope or scanner capable of showing bus traffic. Verify presence/absence of messages from each module and look for intermittent drops or noise.
- Isolate by wiggling harness and connectors while monitoring bus to reproduce the fault. Repair/replace damaged wiring or connectors found.
- If wiring and connectors check good, swap or bench-test suspect module(s) if replacement components or known-good units are available (follow manufacturer guidance).
- After repairs, clear codes, cycle ignition, and road test or reproduce conditions to confirm the fault does not return. Re-scan for codes and verify proper function of infotainment features.
- If intermittent or unclear, consult manufacturer service information for TSBs, software updates, or specific test procedures for U1444.
Likely causes
- Broken or chafed ring wire between the two modules
- Connector pin corrosion or poor mating at the Mozen or head unit connector
- Module failure in Mozen unit or head unit communication circuit
- Missing/incorrect module (vehicle not equipped with Mozen) or incorrect calibration/software
Fault status
Status
Communication ring break detected between Mozen unit and head unit. If vehicle is not equipped with Mozen, code may be ignored. Inspect wiring, connectors, module power/ground and bus signals.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Repair manuals
Manual library for HYUNDAI
84
Browse 84 HYUNDAI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
HYUNDAI
-
HYUNDAI: 2021
-
Accent
-
-
HYUNDAI: 2020
-
Palisade
-
Veloster N
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email