Last updated: Oct 2025
Author: Mike | Mercedes-Benz Diesel DIY Specialist
The P011315 and P010337 codes often appear together in Mercedes-Benz diesel models, including the GLA, A-Class, and C-Class with the 2.1L CDI engine. These codes signal issues with the Intake Air Temperature (IAT) and Mass Air Flow (MAF) sensors โ two critical components that work in tandem to regulate air-fuel mixture.
๐ What Do P011315 and P010337 Mean?
The P011315 code indicates a short circuit or range fault in the Intake Air Temperature Sensor 1, while P010337 signals a fault in the Mass Air Flow Sensor 1 circuit. These two sensors provide vital airflow and temperature data to the ECU. If either fails, the engine may enter limp mode to prevent damage.
Typical Affected Models: GLA 200d, C220d, E250 CDI, Sprinter 2.1 CDI (2005โ2022).
โ๏ธ Common Causes
- Dirty or faulty Mass Air Flow (MAF) sensor element
- Broken wiring to the IAT or MAF sensor
- Corroded electrical connectors near the intake manifold
- Aftermarket sensors with incorrect voltage calibration
- Intake leaks causing erratic air readings
๐งฉ Real Case Study: 2016 Mercedes GLA 220d
A customer reported Check Engine Light and reduced power. Using the iCarsoft CR ULTRA P, the technician confirmed fault codes P011315 and P010337. The air intake sensor assembly was inspected โ the wiring was fine, but the MAF element was clogged with oil residue from the intake breather.
The MAF sensor was carefully cleaned with MAF cleaner spray and reinstalled. After clearing codes and resetting adaptations via CR ULTRA P, the vehicle regained full power โ no further faults returned after 50 miles of driving.
๐งฐ How to Diagnose & Fix Using iCarsoft CR ULTRA P
- Connect the iCarsoft CR ULTRA P to your Mercedes OBD-II port.
- Turn the ignition ON (engine OFF).
- Read stored codes โ confirm P011315 and/or P010337.
- Check live data for MAF flow rate (g/s) and IAT temperature readings.
- If readings are erratic or flatlined, inspect wiring and connectors.
- Clean or replace sensors as needed (OEM parts recommended).
- Use CR ULTRA P to reset adaptations and clear DTCs.
- Start the engine and verify stable idle with proper MAF readings.
๐ก Pro Tips
- Always check the connector pins for green corrosion โ common in older diesels.
- Never use compressed air or physical contact to clean the MAF element.
- After replacing, perform an adaptation reset to recalibrate air readings.
- If both sensors fail simultaneously, check for shared ground or 5V reference short.
โ Extended FAQ โ Mercedes Airflow System Troubleshooting
Q1: Can these codes cause limp mode?
Yes. The ECU reduces power to prevent turbo overboost when it cannot accurately measure airflow.
Q2: Should I replace both IAT and MAF sensors?
Not necessarily. Use live data to verify which sensor is faulty before replacement.
Q3: How can I confirm the MAF sensor is bad?
Compare live MAF data to reference values at idle (2โ6 g/s) and at 3000 RPM (20โ30 g/s). No change = faulty MAF.
Q4: What if cleaning doesnโt work?
If codes return after cleaning, replace the MAF sensor with a genuine OEM part and reset adaptations.
Q5: Can iCarsoft CR ULTRA P perform adaptation resets?
Yes. Navigate to ECU โ Engine โ Adaptation โ Air Mass / Temperature Reset to complete the process.
Q6: Can bad fuel or EGR clogging trigger these codes?
Yes, excessive EGR deposits or oil vapors can contaminate the MAF sensor, leading to inaccurate readings.
โ Conclusion
The combination of P011315 and P010337 typically indicates airflow measurement faults, not major mechanical issues. Using a professional-grade diagnostic tool like iCarsoft CR ULTRA P allows you to diagnose, clean, reset, and confirm sensor functionality โ saving both labor and parts costs.
๐ ๏ธ Get iCarsoft CR ULTRA P Now
