A/C Refrigerant Pressure Sensor "A" Circuit High
The DURAMAX-P0533 (Duramax) diesel fault code means: A/C Refrigerant Pressure Sensor "A" Circuit High. This is a moderate severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0533?
- A/C may not blow cold
- A/C compressor may shut off
- Possible cooling fan running more than usual
What Causes DURAMAX-P0533? (Most Likely First)
- Open signal or ground wire High
- Failed pressure sensor Moderate
- Overcharged system or poor condenser airflow Moderate
Can I Still Drive with DURAMAX-P0533?
Yes, with caution. DURAMAX-P0533 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0533 mean on a Duramax?
P0533 means A/C Refrigerant Pressure Sensor "A" Circuit High. The A/C refrigerant pressure sensor signal is above its normal range, which can mean very high system pressure, an open circuit or a failed sensor.
Is P0533 a Duramax-specific code?
No. P0533 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions GM uses to set it on its diesels are in GM service information.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose DURAMAX-P0533?
Check refrigerant pressure with gauges.
Inspect the sensor connector and harness.
Check that the condenser is clean and the cooling fan works.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0533 as a generic OBD-II code)
P0533 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
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