P2045: Reductant Temperature Sensor A Circuit High
What to do
No immediate driveability effect. Ask for the connector to be inspected rather than the sensor replaced on the code alone.
What this code means
The reductant temperature circuit reads above its valid range — an open circuit or a short to supply, indistinguishable at the module. A connector corroded by years of road spray reads exactly like a broken wire and is the more likely on an underfloor tank.
Likely causes
Start here
- Open circuit in sensor wiring · moderate
- Corroded or loose connector · easy
- Faulty reductant temperature sensor · moderate
Less common
- Road damage to underfloor wiring · moderate
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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