P2520 Fault Code

A/C Request A Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2520 fault code indicates a problem with the A/C Request A circuit being low. This code typically appears when the Engine Control Module (ECM) detects an abnormal voltage level in the A/C request circuit. The circuit is responsible for receiving signals from the A/C switch to activate the air conditioning system. A low signal may mean there's an issue with the wiring, connectors, or the switch itself.

What are the symptoms of the P2520 code?

Common symptoms associated with a P2520 fault code may include:

• The air conditioning system may not operate as intended.
• Continuous A/C compressor cycling or it remains off.
• A/C system blowing warm air instead of cold.
• Illuminated check engine light on the dashboard.

What causes the P2520 code?

Possible causes for the P2520 fault code may include:

• Faulty A/C request switch that is not sending the correct signal.
• Damaged or shorted wiring or connectors in the A/C request circuit.
• Malfunctioning ECM or software glitch leading to incorrect readings.
• Poor ground connection affecting the circuit's operation.

How to fix P2520?

To resolve the P2520 fault code, follow these steps:

• Inspect the A/C request switch for damage or wear and replace if necessary.
• Check wiring and connectors for any signs of damage, corrosion, or shorts.
• Use a multimeter to check the A/C request circuit voltage and compare it to specifications.
• Test the ground connections and ensure they are secure.
• If all components are functioning properly, consider updating or reprogramming the ECM if a software glitch is suspected.