P0150 on Mercedes-Benz C-Class
Factory diagnostic protocol and troubleshooting wire for fault code P0150 specifically for the Mercedes-Benz C-Class (2020–2026, 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP)).
1. Symptoms of P0150 on Mercedes-Benz C-Class
When the Engine Control Module (ECM/PCM) on your Mercedes-Benz C-Class (2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP)) logs fault code P0150, drivers commonly observe:
2. Most Likely Causes on Mercedes-Benz C-Class
Historical warranty claims and technical repair bulletins for Mercedes-Benz C-Class point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Mercedes-Benz C-Class
Identify Bank 2 (the cylinder bank that does NOT contain Cylinder 1). Locate the upstream O2 sensor before the catalytic converter. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Check the 4-wire or 5-wire harness for damage. Measure heater resistance across pins (typically 4–15 ohms). on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Use an O2 sensor socket to remove the old sensor, thread in new OEM replacement, and torque securely. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Clear DTCs and monitor Bank 2 Short Term Fuel Trim (STFT) to verify fuel control restoration. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Equipment for Diagnosing Mercedes-Benz C-Class (P0150)
Mercedes-Benz C-Class OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for Mercedes-Benz C-Class.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
Other Common Fault Codes on Mercedes-Benz C-Class
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Mercedes-Benz C-Class:
4. Mercedes-Benz C-Class P0150 FAQs
What causes code P0150 to trigger on a Mercedes-Benz C-Class?
On the Mercedes-Benz C-Class (2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP)), P0150 is most frequently caused by Failing Bank 2 upstream oxygen sensor or Damaged wiring or melted harness on Bank 2 exhaust manifold.
Where is the OBD-II port located on my Mercedes-Benz C-Class?
On the Mercedes-Benz C-Class, the 16-pin DLC diagnostic connector is located Under driver dash beneath purple/black sliding protective door. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Mercedes-Benz C-Class with code P0150?
Yes, for limited driving. Bank 2 cylinders will operate in open-loop fail-safe mode. Given that P0150 carries a High severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.

