1. What is P061B in BMW 3 Series?

The P061B OBD-II code stands for Internal Control Module Torque Calculation Performance. For the BMW 3 Series G20 (2019-2024)—a best-selling European sports sedan—this code targets the Engine Control Unit (ECU) in its 2.0T B48 engine, standard in 330i, 330i xDrive, and M340i trims (paired with 8-speed ZF 8HP transmission).

The 330i’s ECU calculates real-time torque demands (for acceleration, braking, and traction control) using data from the throttle position sensor, crankshaft position sensor, and turbocharger pressure sensor. P061B triggers when the ECU detects torque calculation errors >15% (vs. expected values) for 5+ seconds—indicating ECU firmware glitches, damaged wiring, or faulty torque-related sensors.

BMW 3 Series Specific Note: This code is widespread in 2020-2023 330i models, per BMW Technical Service Bulletin (TSB) 23-01-05. The B48 engine’s high-output turbo (255HP) places extra load on the ECU; frequent stop-and-go driving (urban commutes) disrupts torque sensor data, leading to calculation mismatches.

2. Common Causes of P061B in 2019-2024 330i

P061B in BMW 330i B48 models stems from ECU torque calculation errors—below are real-world cases diagnosed with the ICARZONE MA200 V6:

• Outdated ECU Firmware (2021 330i xDrive): An owner with 49,000 miles reported hesitation during acceleration and a "Check Engine" light. The MA200 V6’s ECU Firmware Check showed version 1.2.0 (outdated; latest = 2.4.0). Updating firmware via MA200 V6 (per TSB 23-01-05) fixed P061B.
• Damaged Throttle Position Sensor (TPS) Wiring (2020 330i Sport): A Sport trim owner’s P061B reappeared after firmware update. The MA200 V6’s TPS Circuit Test found a broken wire (insulation frayed by engine heat). Repairing with heat-resistant wire (#Dorman 10501) restored torque data flow.
• Faulty Turbocharger Pressure Sensor (2019 330i): A 330i owner’s P061B persisted after wiring repairs. The MA200 V6’s Turbo Pressure Test showed erratic readings (fluctuating 10–20 psi). Replacing the sensor with OEM #13627645477 stabilized torque calculations.
• ECU Internal Glitch (2022 M340i): An M340i owner’s P061B occurred after a battery jump. The MA200 V6’s ECU Reset cleared temporary data corruption, and a follow-up torque test confirmed calculations were within 5% of expected values—P061B did not return.

3. Key Symptoms of P061B in G20 330i

P061B symptoms in the BMW 330i focus on torque delivery and engine responsiveness—watch for these signs that signal ECU calculation errors:

4. BMW 3 Series Trims/Engines Prone to P061B

BMW service data highlights these 2019-2024 3 Series configurations with the highest P061B occurrence rates (all B48/B58 engines):

5. Diagnose P061B with ICARZONE MA200 V6

Diagnose P061B in your BMW 330i B48 accurately with the MA200 V6’s BMW-specific ECU tools. Follow these steps (engine off, key in "ON" position; ensure battery voltage is 12.4–12.7V):

Case Example: A 2021 330i xDrive failed Step 2 (error 18%) and Step 3 (firmware 1.8.0). The MA200 V6’s ECU Firmware Update tool installed version 2.4.0 (matching TSB 23-01-05). A follow-up torque test showed error 3%—P061B cleared, and acceleration hesitation was gone.

6. How to Fix P061B in BMW 330i

Resolve P061B in your 330i with these MA200 V6-verified solutions—tailored to the B48 engine’s ECU and torque system:

1. Update ECU Firmware (Most Common Fix for TSB 23-01-05)

1. Confirm outdated firmware via MA200 V6’s Step 3. Connect MA200 V6 to the 330i’s OBD-II port (under steering wheel) and turn key to "ON."
2. Select "BMW" > "3 Series G20" > "B48 2.0T" > "ECU" > "Firmware Update." The tool will detect the current version and download the latest (v2.4.0 for 2020+ models).
3. Do not turn off the key or disconnect MA200 V6 during the update (takes 25–30 minutes). The tool will alert you when complete (ECU reboots automatically).
4. Run MA200 V6’s Step 2 (torque calculation test) to confirm error <5%. Clear P061B and test drive—verify acceleration is smooth and no hesitation occurs.
5. For 2019 330i models, install firmware v2.2.0 (TSB 22-09-03) instead—matches the older B48 hardware configuration.

2. Repair TPS Wiring Harness

1. Confirm TSB issue via MA200 V6’s Step 4. Locate the TPS: Mounted on the throttle body (driver’s side of the engine, connected to the intake manifold).
2. Disconnect the TPS’s 6-pin electrical connector (press the release tab) and trace the harness to the ECU (runs along the engine bay’s left side).
3. Identify frayed or broken wires—cut out 1 inch of damaged section (use wire cutters) and strip 1/4 inch of insulation from both ends.
4. Splice new 18-gauge heat-resistant wire (#Dorman 10501) using heat-shrink butt connectors. Crimp connectors and apply heat to seal (no exposed wire).
5. Reconnect the TPS connector and retest resistance with MA200 V6 (Step 4). Clear P061B and test drive—ensure torque delivery is consistent during acceleration.

3. Replace Turbocharger Pressure Sensor

1. Confirm sensor fault via MA200 V6’s turbo pressure test. Locate the sensor: Mounted on the turbocharger compressor housing (passenger side of the engine).
2. Disconnect the sensor’s 3-pin electrical connector and remove the mounting bolt (8mm socket).
3. Pull the old sensor straight out—inspect the pressure port for carbon buildup (clean with compressed air if minor).
4. Install an OEM turbo pressure sensor:
   • 2019-2021 330i: #13627645477
   • 2022-2024 330i: #13627648951 (updated pressure range)
   Torque the mounting bolt to 10 ft-lbs.
5. Reconnect the electrical connector and run MA200 V6’s turbo pressure test (target: stable 15–20 psi during acceleration). Clear P061B and verify torque calculation error <5%.

7. P061B Repair Costs & Maintenance Tips

P061B repair costs for the BMW 330i B48 vary by cause. Use this table to budget:

Maintenance Tips for BMW 330i Owners

• 330i xDrive (urban drivers): Update ECU firmware annually via MA200 V6—ensures compatibility with B48’s torque demands and addresses TSB 23-01-05 gaps.
• Inspect TPS wiring during oil changes—wrap exposed sections with heat-resistant tape (#3M 33+) to prevent engine heat damage (critical for 330i Sport).
• Use Top Tier detergent gasoline (91+ octane)—low-quality fuel causes turbo pressure fluctuations, leading to torque calculation errors.
• Avoid jump-starting the battery unless necessary—voltage spikes can corrupt ECU data (use a battery tender for low-charge situations).
• Perform the MA200 V6’s Torque System Health Check every 15,000 miles — monitor calculation accuracy and sensor data to catch issues before P061B triggers.

8. BMW 3 Series-Specific FAQs