P2521

A/C Request A Circuit High

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$6–56 (est.)

Symptoms

Air conditioner won't turn on
Reduced cooling efficiency
Hot air from vents
Air conditioner light flashing
Increased fuel consumption

Causes

Short circuit to positive
Faulty A/C relay
Wiring harness damage
Problems with the air conditioning control unit
Refrigerant pressure sensor malfunction

How to Fix

Check fuses and relays of the air conditioner
Inspect the wiring harness for damage
Check the resistance of the A/C request circuit
Diagnose the air conditioning control unit
If necessary, replace faulty components

Related codes

P0532 P0533 P0740