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.
- 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
-
Check B circuit voltage for constant high signal
-
Inspect rear A/C relay contacts
-
Test rear climate control module output
-
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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