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2012 AUDI A3

2.0L TDI I4FWDAUTOMATICdieselturbo
4 active safety recalls on this vehicle — view recalls
Repairs0Labor595Torque4768Fluid6DTC778Battery0Maintenance0Recalls4
P3835moderate severityPowertrain

DEF Tank Level Sensor Malfunction

on 2012 Audi A3 2.0L TDI I4 · FWD

What this code means

The DEF tank level sensor is reporting incorrect or no reading.

Symptoms

  • DEF level gauge inaccurate
  • False low DEF warning
  • Cannot determine DEF level
  • Potential unnecessary derate warning
  • Service message for DEF

Common causes

  • Level sensor float stuck
  • Sensor wiring corrosion
  • Crystallized DEF on sensor
  • Tank sender unit failure
  • Short circuit in sensor

Diagnostic steps

  1. Read DEF level PID and compare to actual
  2. Inspect DEF tank sender unit
  3. Check sensor wiring for corrosion
  4. Test sensor resistance range
  5. Add known quantity of DEF and check reading

Repair notes

Replace DEF tank level sender unit. Clean DEF tank if crystallization is present.

Other Powertrain codes on this vehicle

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