P2524 low

A/C Request B Circuit High

The P2524 code means the vehicle's onboard diagnostic system has detected: A/C Request B Circuit High. This is a low severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
moderate
Estimated cost
$100 - $400 (parts and labor)
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Common Symptoms

  • Rear A/C always requesting compressor engagement
  • Compressor running when rear A/C is off
  • Higher fuel consumption
  • Check engine light on

Probable Causes (Ranked by Likelihood)

  • Short to voltage in rear A/C request wiring Very High
  • Rear A/C relay stuck closed High
  • Rear climate module sending constant request signal Moderate
  • Wiring harness pinched at body panel Low

Step-by-Step Diagnostic Procedure

  1. Check B circuit voltage for constant high signal

  2. Inspect rear A/C relay contacts

  3. Test rear climate control module output

  4. Trace wiring for pinch points at body panels

Frequently Asked Questions

Why is my compressor running when I only have front heat on?

P2524 means the rear A/C request signal is stuck high, constantly telling the ECM to run the compressor even when rear A/C is not selected.

Will this increase my fuel costs?

Yes. The A/C compressor adds load to the engine, increasing fuel consumption by roughly 5-15% when running continuously.

Can I disconnect the rear A/C to save fuel until repaired?

Removing the rear A/C relay or fuse is a temporary solution, but it will also disable rear A/C when you actually want it.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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