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Home / DTC / U0466 — Invalid Data Received From HVAC Control Module - Rear

U0466 — Invalid Data Received From HVAC Control Module - Rear

Detailed page for trouble code U0466.

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U0466

Generic U — Network/User

Invalid Data Received From HVAC Control Module - Rear

Brand: Generic
Type: U — Network/User
Views: UK: 16 EN: 25 RU: 18
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty rear HVAC control module (hardware or firmware)
  • Damaged, corroded, or loose connectors at the rear HVAC module
  • Open, shorted, or intermittent wiring on the HVAC communication or power circuits
  • CAN/LIN bus wiring fault, missing termination, or excessive noise
  • Low or unstable battery/charging system voltage during communication
  • Software mismatch, incomplete calibration, or incorrect module programming

Symptoms

  • Rear HVAC functions inoperative or unresponsive (blower, temperature, mode)
  • Rear temperature setpoint ignored or displayed incorrectly
  • HVAC fault message or warning lamp on dash or infotainment
  • Intermittent or erratic rear climate control behavior
  • Multiple communication or U-codes present in networked modules

What to check

  • Connect a compatible scan tool; read freeze frame data and note related U-codes
  • Check for the rear HVAC module's presence on the network (module IDs/addresses)
  • Verify battery voltage is within specification (engine off and running)
  • Inspect connectors at rear HVAC module for corrosion, bent pins, or water intrusion
  • Visually inspect CAN/LIN wiring harness for damage, chafing, or repairs
  • Measure CAN high/low idle voltages (~2.5 V single-ended; ~0 V differential) with backprobe or scope

Signal parameters

  • CAN High / CAN Low bus voltages (idle ≈ 2.5 V each; differential ≈ 0 V)
  • Presence and frequency of HVAC rear CAN messages (message IDs and update rate)
  • Rear HVAC setpoint data bytes (temperature setpoint, blower command, mode)
  • Blower motor command vs feedback (rpm or PWM duty) if available
  • Blend/door actuator position feedback values
  • Rear temperature sensor voltage or resistance values

Diagnostic algorithm

  1. Use a scan tool to record all U-codes and related events across modules; note freeze frame and occurrence conditions.
  2. Verify battery and charging system voltages; poor voltage can cause communication errors.
  3. Inspect rear HVAC module connector(s) and harness for corrosion, water intrusion, damaged pins, or repair splice points; repair as needed.
  4. With ignition on, confirm the rear HVAC module is present on the bus. If not present, check module power (switched and unswitched) and ground circuits for continuity and correct voltage.
  5. Check CAN bus integrity: measure CAN-H/CAN-L voltages, and use a scope or CAN bus analyzer to confirm healthy message traffic and correct termination. Look for missing or malformed HVAC messages.
  6. Wiggle test wiring harness while monitoring network and rear HVAC messages to find intermittent faults.
  7. If wiring and connectors are good and bus traffic is healthy but data is invalid, attempt module soft reset (clear DTCs) and re-check. If fault returns, check for available software updates or reflashing procedures from manufacturer.
  8. If software update does not resolve and diagnostics point to the module, replace the rear HVAC control module and reprogram/configure per vehicle procedures.
  9. After repairs, clear codes, cycle ignition, and perform functional test of rear HVAC. Road-test and monitor network for recurrence.
  10. If fault persists and multiple modules affected, inspect gateway/BODY control module and consider broader network diagnostics.

Likely causes

  • Poor connector or ground at the rear HVAC module
  • Intermittent/open/shorted CAN high/low between rear HVAC and gateway
  • Failed rear HVAC module
  • Bus termination or wiring harness damage (pinched/chewed/wet connector)
  • Module software or calibration mismatch after replacement or update

Fault status

⚠️ Status
Invalid data received from rear HVAC control module — communication or data integrity fault detected between the rear HVAC module and the vehicle network.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1-3 hours

Similar codes

U0460 U0462 U0464 U0465 U0469 U0073
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Code

U0466

HYUNDAI U — Network/User

Invalid Data Received From HVAC Control Module Rear

Brand: HYUNDAI
Type: U — Network/User
Views: UK: 8 EN: 15 RU: 10
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty rear HVAC control module (hardware or firmware)
  • Damaged, corroded, or loose connectors at the rear HVAC module
  • Open, shorted, or intermittent wiring on the HVAC communication or power circuits
  • CAN/LIN bus wiring fault, missing termination, or excessive noise
  • Low or unstable battery/charging system voltage during communication
  • Software mismatch, incomplete calibration, or incorrect module programming

Symptoms

  • Rear HVAC functions inoperative or unresponsive (blower, temperature, mode)
  • Rear temperature setpoint ignored or displayed incorrectly
  • HVAC fault message or warning lamp on dash or infotainment
  • Intermittent or erratic rear climate control behavior
  • Multiple communication or U-codes present in networked modules

What to check

  • Connect a compatible scan tool; read freeze frame data and note related U-codes
  • Check for the rear HVAC module's presence on the network (module IDs/addresses)
  • Verify battery voltage is within specification (engine off and running)
  • Inspect connectors at rear HVAC module for corrosion, bent pins, or water intrusion
  • Visually inspect CAN/LIN wiring harness for damage, chafing, or repairs
  • Measure CAN high/low idle voltages (~2.5 V single-ended; ~0 V differential) with backprobe or scope

Signal parameters

  • CAN High / CAN Low bus voltages (idle ≈ 2.5 V each; differential ≈ 0 V)
  • Presence and frequency of HVAC rear CAN messages (message IDs and update rate)
  • Rear HVAC setpoint data bytes (temperature setpoint, blower command, mode)
  • Blower motor command vs feedback (rpm or PWM duty) if available
  • Blend/door actuator position feedback values
  • Rear temperature sensor voltage or resistance values

Diagnostic algorithm

  1. Use a scan tool to record all U-codes and related events across modules; note freeze frame and occurrence conditions.
  2. Verify battery and charging system voltages; poor voltage can cause communication errors.
  3. Inspect rear HVAC module connector(s) and harness for corrosion, water intrusion, damaged pins, or repair splice points; repair as needed.
  4. With ignition on, confirm the rear HVAC module is present on the bus. If not present, check module power (switched and unswitched) and ground circuits for continuity and correct voltage.
  5. Check CAN bus integrity: measure CAN-H/CAN-L voltages, and use a scope or CAN bus analyzer to confirm healthy message traffic and correct termination. Look for missing or malformed HVAC messages.
  6. Wiggle test wiring harness while monitoring network and rear HVAC messages to find intermittent faults.
  7. If wiring and connectors are good and bus traffic is healthy but data is invalid, attempt module soft reset (clear DTCs) and re-check. If fault returns, check for available software updates or reflashing procedures from manufacturer.
  8. If software update does not resolve and diagnostics point to the module, replace the rear HVAC control module and reprogram/configure per vehicle procedures.
  9. After repairs, clear codes, cycle ignition, and perform functional test of rear HVAC. Road-test and monitor network for recurrence.
  10. If fault persists and multiple modules affected, inspect gateway/BODY control module and consider broader network diagnostics.

Likely causes

  • Poor connector or ground at the rear HVAC module
  • Intermittent/open/shorted CAN high/low between rear HVAC and gateway
  • Failed rear HVAC module
  • Bus termination or wiring harness damage (pinched/chewed/wet connector)
  • Module software or calibration mismatch after replacement or update

Fault status

⚠️ Status
Invalid data received from rear HVAC control module — communication or data integrity fault detected between the rear HVAC module and the vehicle network.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1-3 hours

Similar codes

U0460 U0462 U0464 U0465 U0469 U0073
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

U0466

LAND ROVER U — Network/User

Invalid data received from the ventilation and air control module conditioned for rear heating

Brand: LAND ROVER
Type: U — Network/User
Views: UK: 7 EN: 17 RU: 7
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty rear HVAC control module (hardware or firmware)
  • Damaged, corroded, or loose connectors at the rear HVAC module
  • Open, shorted, or intermittent wiring on the HVAC communication or power circuits
  • CAN/LIN bus wiring fault, missing termination, or excessive noise
  • Low or unstable battery/charging system voltage during communication
  • Software mismatch, incomplete calibration, or incorrect module programming

Symptoms

  • Rear HVAC functions inoperative or unresponsive (blower, temperature, mode)
  • Rear temperature setpoint ignored or displayed incorrectly
  • HVAC fault message or warning lamp on dash or infotainment
  • Intermittent or erratic rear climate control behavior
  • Multiple communication or U-codes present in networked modules

What to check

  • Connect a compatible scan tool; read freeze frame data and note related U-codes
  • Check for the rear HVAC module's presence on the network (module IDs/addresses)
  • Verify battery voltage is within specification (engine off and running)
  • Inspect connectors at rear HVAC module for corrosion, bent pins, or water intrusion
  • Visually inspect CAN/LIN wiring harness for damage, chafing, or repairs
  • Measure CAN high/low idle voltages (~2.5 V single-ended; ~0 V differential) with backprobe or scope

Signal parameters

  • CAN High / CAN Low bus voltages (idle ≈ 2.5 V each; differential ≈ 0 V)
  • Presence and frequency of HVAC rear CAN messages (message IDs and update rate)
  • Rear HVAC setpoint data bytes (temperature setpoint, blower command, mode)
  • Blower motor command vs feedback (rpm or PWM duty) if available
  • Blend/door actuator position feedback values
  • Rear temperature sensor voltage or resistance values

Diagnostic algorithm

  1. Use a scan tool to record all U-codes and related events across modules; note freeze frame and occurrence conditions.
  2. Verify battery and charging system voltages; poor voltage can cause communication errors.
  3. Inspect rear HVAC module connector(s) and harness for corrosion, water intrusion, damaged pins, or repair splice points; repair as needed.
  4. With ignition on, confirm the rear HVAC module is present on the bus. If not present, check module power (switched and unswitched) and ground circuits for continuity and correct voltage.
  5. Check CAN bus integrity: measure CAN-H/CAN-L voltages, and use a scope or CAN bus analyzer to confirm healthy message traffic and correct termination. Look for missing or malformed HVAC messages.
  6. Wiggle test wiring harness while monitoring network and rear HVAC messages to find intermittent faults.
  7. If wiring and connectors are good and bus traffic is healthy but data is invalid, attempt module soft reset (clear DTCs) and re-check. If fault returns, check for available software updates or reflashing procedures from manufacturer.
  8. If software update does not resolve and diagnostics point to the module, replace the rear HVAC control module and reprogram/configure per vehicle procedures.
  9. After repairs, clear codes, cycle ignition, and perform functional test of rear HVAC. Road-test and monitor network for recurrence.
  10. If fault persists and multiple modules affected, inspect gateway/BODY control module and consider broader network diagnostics.

Likely causes

  • Poor connector or ground at the rear HVAC module
  • Intermittent/open/shorted CAN high/low between rear HVAC and gateway
  • Failed rear HVAC module
  • Bus termination or wiring harness damage (pinched/chewed/wet connector)
  • Module software or calibration mismatch after replacement or update

Fault status

⚠️ Status
Invalid data received from rear HVAC control module — communication or data integrity fault detected between the rear HVAC module and the vehicle network.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1-3 hours

Similar codes

U0460 U0462 U0464 U0465 U0469 U0073
Workshop Manuals

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3

Land Rover Defender 300Tdi — Workshop Manual (1996 model year)

Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

199,00 UAH
Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
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Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
Short description

Workshop Manual Supplement and Body Repair Manual for the Land Rover Defender. Includes general specifications, maintenance schedules, tuning data and step‑by‑step repair procedures for engine, transmission, suspension, brakes, electrical and body repairs. Covers Defender models from 1999 and 2002 model years.

199,00 UAH
Contents
Key sections:
  • 01 - INTRODUCTION
  • - Introduction
  • - Dimensions
  • - References
  • - Repairs and replacements
  • - Poisonous substances
  • - Fuel handling precautions
  • - Synthetic rubber
  • - Recommended sealants
  • - Used engine oil precautions
  • - Accessories and conversions
  • - Wheels and tyres
Buy

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Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

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199,00 UAH
Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
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