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2018 AUDI A6
3.0L Supercharged V6•AWD•AUTOMATIC•gas•supercharged
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor507Torque3472Fluid7DTC1143Battery1Maintenance0Recalls2
U0165low severityNetwork

Lost Communication with Rear HVAC Control Module

on 2018 Audi A6 3.0L Supercharged V6 · AWD

What this code means

Cannot communicate with the rear climate control zone module.

Symptoms

  • Rear A/C not working
  • Rear climate controls unresponsive
  • No rear heat
  • Rear blower not running

Common causes

  • Rear HVAC module failure
  • CAN bus wiring
  • Module power loss
  • Fuse blown
  • Rear blower motor issue

Diagnostic steps

  1. Check rear HVAC module fuse
  2. Test power and ground
  3. Check CAN wiring
  4. Test rear blower motor
  5. Inspect rear climate control panel

Repair notes

Check fuses for rear HVAC system. Rear module wiring runs through pillars.

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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