A/C Request ‘A’ Circuit High
Table of contents
P2521 MERCEDES-BENZ Possible Causes
- Low refrigerant
- Too much refrigerant
- Faulty Low Side Pressure Sensor
- Low Side Pressure Sensor harness is open or shorted
- Low Side Pressure Sensor circuit poor electrical connection
How do I fix code P2521 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.
Cost of diagnosing the P2521 MERCEDES-BENZ code
The cost of diagnosing the P2521 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)
P2521 MERCEDES-BENZ Description
The Powertrain Control Module (PCM) monitors the refrigerant pressure through the Air Condition (A/C) Pressure Sensor. The PCM supplies a 5V reference and a low reference to the sensor. Changes in the A/C refrigerant pressure causes the sensor signal to the PCM to vary. When the pressure is high, the signal is high. When the pressure is low, the signal is low. The PCM sets the OBII code when the signal from the sensor is out of factory specifications.