Reductant Injection Air Pressure Sensor Circuit
The P2037 code means the vehicle's onboard diagnostic system has detected: Reductant Injection Air Pressure Sensor Circuit. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $200 - $600 (parts and labor)
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Common Symptoms
- Check Engine Light on
- SCR system malfunction warning
- Reduced engine power
- Increased NOx emissions
- DEF system warning light
Probable Causes (Ranked by Likelihood)
- Faulty reductant injection air pressure sensor Very High
- Clogged air supply line to DEF injector High
- Corroded sensor connector Moderate
- Air pump failure affecting DEF system Moderate
- PCM circuit fault Low
Step-by-Step Diagnostic Procedure
-
Confirm P2037 with freeze frame data
-
Inspect DEF injection air pressure sensor and connector
-
Check air supply line to DEF injector for blockage
-
Measure sensor signal voltage and compare to specification
Frequently Asked Questions
What does P2037 mean?
P2037 indicates a problem with the air pressure sensor in the reductant (DEF) injection system, which ensures proper atomization of diesel exhaust fluid for NOx reduction.
Can I drive with a P2037 code?
You can drive short distances, but the SCR system will not function properly, increasing NOx emissions and potentially triggering a speed limiter on some vehicles.
How much does it cost to fix P2037?
Repairs typically cost $200 to $600 for sensor replacement or air supply line cleaning.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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