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2009 AUDI A8
4.2L V8•AWD•AUTOMATIC•gas
1 active safety recall on this vehicle — view recalls
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Repairs0Labor488Torque2170Fluid9DTC1840Battery1Maintenance0Recalls1
P0493moderate severityPowertrain

Cooling Fan Speed

on 2009 Audi A8 4.2L V8 · AWD

What this code means

The PCM has detected that the cooling fan speed does not match the commanded value. This can lead to inadequate engine cooling.

Symptoms

  • Engine overheating
  • Fan running too slow or fast
  • Warning lamp on

Common causes

  • Faulty cooling fan motor
  • Faulty fan control module
  • Damaged wiring or connector
  • Faulty PCM

Diagnostic steps

  1. Scan for stored codes
  2. Compare commanded vs actual fan speed
  3. Inspect fan wiring and connectors
  4. Test fan module and motor
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