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B0227
Difficulty: EasyTime: 1-2 hoursUpdated: March 10, 2025

Understanding B0227 — Wiper Relay Circuit

When your 2019 Audi A3 triggers diagnostic trouble code B0227 (Wiper Relay Circuit), it indicates a specific malfunction within the windshield wiper and washer system. This code specifically relates to wiper relay circuit and requires systematic diagnosis to identify the root cause.

Modern wiper systems use electric motors, gear trains, and electronic controls to provide variable speed operation, intermittent timing, and automatic rain sensing. When this system detects a fault, diagnostic trouble codes are stored to aid technicians in identifying the issue.

Common Symptoms

Drivers typically experience one or more of the following symptoms when B0227 is active:

  • Wipers inoperative at one or more speeds
  • Wipers not returning to park position
  • Intermittent or incorrect wiper timing
  • Washer pump not working
  • Rain sensor malfunction
  • Washer fluid low warning

The wipers may work in some modes but not others, or may fail to stop in the correct position when turned off.

Affected Components

The Wiper Relay Circuit fault can stem from failures in several wiper system components:

Wiper Motor: The wiper motor contains a DC motor, gear train, and limit switches. Motor failures can occur from worn brushes, failed bearings, or corroded commutators.

Wiper Linkage: Connecting arms transfer motor rotation to the wiper blades. Bent or worn linkage causes uneven wiping or juddering motion.

Wiper Control Module: Electronic controls manage wiper functions based on inputs from the stalk switch and rain sensor. Module failures can cause random operation or complete system failure.

Rain Sensor: Located behind the rearview mirror, these sensors detect moisture on the windshield using infrared light. Sensor failures cause automatic wiper systems to malfunction.

Stalk Switch: The turn signal/wiper stalk provides inputs to the body control module. Contact wear inside the switch causes intermittent or incorrect operation.

Washer Pump: The washer pump is a small electric motor that pushes fluid through hoses to the windshield or headlight washers. Pumps can fail from clogged filters or motor burnout.

Washer Fluid Level Sensor: Some vehicles monitor washer fluid level and trigger warnings when low. Float-style sensors can stick or fail electrically.

Wiring and Connectors: Wiper circuits experience high current draw and constant flexing. Connectors can overheat, melt, or corrode.

Diagnosis Procedure

Follow these steps to properly diagnose B0227 in your 2019 Audi A3:

Step 1: Retrieve Diagnostic Codes

Connect an OBD-II scanner and record all stored codes, including pending and history codes. Note which wiper function is affected.

Step 2: Visual Inspection

Inspect visible wiper components:

  • Check wiper blades for wear, damage, and proper contact
  • Inspect wiper arms for bent or damaged sections
  • Verify washer fluid level and condition
  • Check washer hoses for kinks or disconnects
  • Inspect linkage for bent or disconnected components

Step 3: Check for Technical Service Bulletins

Many manufacturers release TSBs addressing known wiper issues. Search for B0227 TSBs for your 2019 Audi A3 to see if a known fix exists.

Step 4: Functional Testing

Test wiper operation in all modes:

  • Low speed
  • High speed
  • Intermittent (multiple delay settings)
  • Mist
  • Washer operation
  • Rear wiper (if equipped)

Note any inconsistencies or complete failures.

Step 5: Pinpoint Testing

Use a digital multimeter to test electrical circuits. Check for:

  • Voltage at the wiper motor connector
  • Ground circuit continuity
  • Control signal from body module
  • Resistance of motor windings
  • Washer pump operation

Step 6: Module Testing

If no external faults are found, the wiper control module may be faulty. Some modules are integrated with the body control module.

Repair Solutions

Wiper Motor Replacement: Wiper motors are relatively expensive but straightforward to replace. After replacement, verify proper park position and wipe pattern.

Linkage Replacement: Bent linkage can often be straightened, but worn pivot points require replacement. New linkage comes complete with arms.

Washer Pump Replacement: Washer pumps are inexpensive and easy to replace. Check the filter screen on the pump intake when servicing.

Switch Replacement: Stalk switches require removal of the steering column covers for access. After replacement, verify all functions operate correctly.

Rain Sensor Replacement: Rain sensors are typically bonded to the windshield or mounted behind the mirror. Some vehicles require recalibration after sensor replacement.

Prevention and Maintenance

Keep wiper systems working properly:

  • Replace wiper blades every 6-12 months
  • Clean blades with window cleaner regularly
  • Use proper windshield washer fluid (not water)
  • Keep washer fluid reservoir filled
  • Clear snow and ice from wipers before driving
  • Avoid running wipers on dry glass

Proper wiper function keeps your 2019 Audi A3 safe in inclement weather.