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P05712021 Model Year TelemetryHigh Severity

P0571 on 2021 Audi A6

Brake Switch A Circuit Malfunction

Technical troubleshooting wire for fault code P0571 specifically tailored for the 2021 Audi A6. Includes wiring sensor pinouts, freeze frame PID parameters, and step-by-step diagnostic tree.

2021 Engine Control Module (ECM) Specific Calibration
Audi A62021 A6
2021 Audi A6
Sedan3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro
2021 Stats
Vehicle
2021 A6
3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro
ECU Subsystem
Automotive OBD-II
SAE Mode $01 & $02
Est. Repair Cost
$70 - $180 (DIY: $15 - $40)
OEM Parts & DIY
Urgency Level
High
Drivable (Short)
Switch A6 Model Year for P0571

Common 2021 A6 Symptoms

  • System alert or indicator light illuminated (P0571)
  • Intermittent performance throttling or unexpected operation halts
  • Audible sensor relay clicking or anomalous status telemetry in dashboard logs
  • Degraded operational throughput or error dialog popups on startup
  • Readiness monitors failing state emissions or system compliance audits

Likely Root Causes on 2021 A6

  • Component aging, oxidation, or degraded internal circuit element (Brake Pedal Position Switch)
  • Wiring harness abrasion, loose terminal pin, or ground voltage float
  • Outdated firmware microcode or incompatible software driver update
  • Thermal stress or excessive operational duty-cycle fatigue
  • Contamination from carbon buildup, moisture ingress, or dirty filtration

Step-by-Step Fix Protocol for 2021 Audi A6

Step 1: Scan & Record Freeze Frame Data

Connect an OBD-II scanner to the DLC port under the driver dashboard. Record engine RPM, Short Term / Long Term Fuel Trim (STFT/LTFT), and engine coolant temperature at the moment P0571 set.

Step 2: Inspect Wiring Harness & Pin Voltages

Inspect the sensor connector on the 2021 A6 engine bay. Use a multimeter to verify reference voltage (5.0V / 12.0V) and ground continuity.

Step 3: Component Replacement & PCM Reset

Replace the verified defective component using OEM or equivalent grade parts. Clear DTC P0571 and complete an EPA drive cycle to verify readiness monitors set to READY.

Recommended Parts & Testing Tools

Equipment for Diagnosing 2021 Audi A6 (P0571)

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Direct-Fit Replacement Part

2021 Audi A6 OEM Replacement Sensor

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Direct-fit replacement assembly engineered to OEM tolerances for 2021 Audi A6.

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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
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BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

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