P2044 code meaning
Reductant Temperature Sensor A Circuit Low
Powertrain system Generic code P20xx codes Check engine light
What P2044 means
P2044 is set when the signal of reductant temperature sensor A sits below its valid voltage window. As with other NTC thermistors, a low voltage corresponds to a hot reading, so a signal wire touching ground makes the fluid look extremely hot. Deutz lists P2044-00 as a grounded signal of the SCR-side DEF temperature input (SPN 4337) on the EMR L1 main and secondary ECU, kept apart from the tank sensor, whose low fault is P205C. No public table gives voltage or time limits for P2044; CARB only requires out of range and circuit checks for every input that feeds an emission control (13 CCR 1968.2 (f)(15.2.1)). A false hot value can switch off DEF heating in the cold, so frozen lines may follow. Measure the sensor and look for chafing before replacing parts.
P2044 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2044
- MIL and DEF warning
- Scan tool shows an implausibly high DEF temperature
- Lines may freeze because heating stays off
Common causes of P2044
- Most likelySignal wire chafed through to ground
- PossibleSensor shorted internally (resistance near zero)
- PossibleDEF residue in the connector bridging signal and ground
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Reductant temperature sensor
What each part of P2044 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| 44 | The exact fault in that area. |
What to do next
- Note P2044 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2044
What does P2044 mean?
P2044 means "Reductant Temperature Sensor A Circuit Low". P2044 is set when the signal of reductant temperature sensor A sits below its valid voltage window. It is a generic code, so it means the same on every make.
Is it safe to drive with P2044?
Drive gently and only to a workshop. With P2044 the car can go into limp mode (reduced power) to protect itself.
Will P2044 fail an emissions test?
Yes, it can. P2044 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2044 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P2044 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.