P2044: Reductant Temperature Sensor A Circuit Low
What to do
No driveability effect immediately. Ask for the underfloor wiring to be inspected as well as the sensor, since salt damage there is common on these systems.
What this code means
The reductant temperature circuit reads below its valid range, normally a short to ground. Depending on the sensor's characteristic the module reads this as either impossibly hot or impossibly cold fluid, and both are implausible enough that it distrusts the value and suspends dosing rather than acting on it.
The tank sits under the vehicle and its harness runs with it, so road salt — which these vehicles meet in exactly the weather where the heater matters — is a leading cause and is found by inspection rather than by testing at the module.
Likely causes
Start here
- Wiring shorted to ground · moderate
- Road damage to underfloor wiring · moderate
- Faulty reductant temperature sensor · moderate
Less common
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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