Barometric Pressure Circuit High
The DURAMAX-P2229 (Duramax) diesel fault code means: Barometric Pressure Circuit High. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $100-$2,500 depending on component
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Common Symptoms
- Check Engine Light illuminated
- Reduced engine performance
- Limp mode or 'Service Engine' message
- Rough idle or stalling (sensor-related)
- Hard shift or slip (transmission codes)
Probable Causes (Ranked by Likelihood)
- BARO sensor open Very Likely
- Wiring harness damage or connector corrosion Likely
- Sensor end-of-life (high mileage engines) Possible
- Control module internal fault Less Likely
Step-by-Step Diagnostic Procedure
Connect scan tool and capture freeze frame data showing when fault occurred
Verify battery voltage and all PCM grounds are clean and tight
Back-probe the suspect sensor / circuit with a DMM and compare to spec
Inspect wiring harness for abrasion, chafing, or rodent damage
After repair, clear code and drive a complete drive cycle to confirm fix
Frequently Asked Questions
What is P2229 on a Duramax?
Duramax code P2229 (Barometric Pressure Circuit High) is a moderate-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. A bad 5V reference (P0642/P0643) will cascade into multiple unrelated sensor codes — always diagnose reference voltage first.
Is a Duramax P2229 safe to drive?
Depends on severity — sensor codes usually drivable; PCM/transmission codes should be repaired before continued use.
How much does it cost to fix P2229 on a Duramax?
Component repairs typically $100-$500. Control module replacement $800-$2,500.
P2229 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: