What Does P2044 Mean?
The reductant temperature sensor is reading abnormally low voltage, indicating either extremely cold temperatures, a short to ground, or sensor circuit fault. This prevents proper DEF system management and freeze protection.
Common Causes
35%
Short to ground in sensor signal wire
30%
Failed temperature sensor with internal short circuit
20%
Damaged sensor connector causing ground short
10%
Chafed wiring harness grounding signal circuit
5%
Moisture intrusion in sensor or connector creating ground path
Diagnostic Steps
1
Step 1: Disconnect temperature sensor and observe scan tool reading (should read very high/open)
2
Step 2: Measure resistance between sensor signal wire and ground at ECM connector
3
Step 3: Inspect sensor connector for moisture, corrosion, or pin-to-pin shorts
4
Step 4: Check wiring harness routing for chafe points or damage near grounded components
5
Step 5: Test sensor resistance and compare to temperature/resistance specifications
Estimated Repair Cost
$180 - $520
Parts + labor, varies by vehicle and location
The reductant temperature sensor is reading abnormally low voltage, indicating either extremely cold temperatures, a short to ground, or sensor circuit fault. This prevents proper DEF system management and freeze protection.
The most common cause of P2044 (Reductant Temperature Sensor Circuit Low) is: Short to ground in sensor signal wire
Typical repair costs for P2044 range from $180 to $520, depending on the vehicle, location, and whether you do it yourself or go to a shop.
DEF system may not operate correctly, particularly in cold weather. Vehicle may prevent restart if system believes DEF is frozen, or may experience power reduction and derate conditions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2044 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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