P2522 — Issue with air-conditioning request circuit B

The code indicates a problem in the secondary air-conditioning control circuit. It appears when the vehicle's computer detects an electrical fault or communication issue with the AC system's request signal. This can cause the AC compressor or related components to not engage properly, affecting cooling performance.

Common causes

The cause is almost always one of a few things. Here they are — P2522 rarely comes from anything outside this list:

• Faulty AC request relay or fuse
• Damaged wiring or connector in AC circuit B
• Defective AC control module or sensor
• Blown fuse related to AC system
• Corroded or loose electrical connections

Where to start

In the order a sensible mechanic would work — the cheap checks first, the expensive replacements only after:

1. Check and replace blown fuses related to AC
2. Inspect and repair wiring and connectors in AC circuit B
3. Test and replace faulty AC request relay
4. Diagnose and repair or replace AC control module
5. Replace AC compressor or related hardware if needed

That is what holds for P2522 in general. From here it depends on your engine — tell me which car it is and what it does, and I will give you the steps for it: real procedures, torque figures and diagrams instead of general advice.