What Does P2041 Mean?
The reductant injection air pressure sensor signal is intermittently dropping out or fluctuating erratically. This suggests a loose connection, damaged wiring, or an intermittently failing sensor in the DEF dosing air supply system.
Common Causes
40%
Loose or corroded electrical connector at air pressure sensor
30%
Intermittent sensor failure with internal connection issues
20%
Damaged or chafed wiring harness creating intermittent open/short
10%
Vibration-induced connector or sensor mounting issues
Diagnostic Steps
1
Step 1: Inspect air pressure sensor connector for corrosion, moisture, and proper pin seating
2
Step 2: Monitor sensor signal voltage with scan tool while moving harness and connector
3
Step 3: Check sensor mounting security and vibration isolation
4
Step 4: Inspect wiring harness routing for potential chafe points or stress areas
5
Step 5: Test sensor voltage response during actual reductant injection cycles
Estimated Repair Cost
$150 - $550
Parts + labor, varies by vehicle and location
The reductant injection air pressure sensor signal is intermittently dropping out or fluctuating erratically. This suggests a loose connection, damaged wiring, or an intermittently failing sensor in the DEF dosing air supply system.
The most common cause of P2041 (Reductant Injection Air Pressure Sensor "A" Circuit Intermittent) is: Loose or corroded electrical connector at air pressure sensor
Typical repair costs for P2041 range from $150 to $550, depending on the vehicle, location, and whether you do it yourself or go to a shop.
May cause improper DEF dosing leading to emissions violations. Vehicle may experience power reduction and progressive derate warnings if not addressed promptly.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2041 to identify the root cause.
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Quick Info
Category
Powertrain
System
Emissions Control (SCR)
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
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