HO2S Heater Control Circuit Bank 2 Sensor 1
Table of contents
P0050 MERCEDES-BENZ Possible Causes
- Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1
- Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 harness is open shorted to ground
- Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How do I fix code P0050 MERCEDES-BENZ?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
- Mercedes Benz Code = 0447 (Left O2 sensor, before TWC): Open circuit (P0050)
Cost of diagnosing the P0050 MERCEDES-BENZ code
The cost of diagnosing the P0050 MERCEDES-BENZ code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0050 MERCEDES-BENZ Description
Oxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM). In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The ECM controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The ECM controls the heater element circuit by allowing current flow to ground.
This fault code is stored in the engine control module when the current flow through the oxygen sensor heater circuit is not as expected. The ECM uses a comparator to measure the voltage drop across a known resistor, using this value the system can calculate the current flow within the circuit. The supply voltage to the component must be investigated. The resistance of the heater element should also be tested. A resistance of approximately 8 Ohms to 15 Ohms is satisfactory. Due to the location of this component the electrical connector can become contaminated with splash from the road. Separate the electrical connector and inspect the pins for corrosion.