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Reductant Temperature Sensor

Measures the temperature of the urea solution, which decides whether dosing is attempted at all — the fluid freezes at around minus eleven degrees and dosing it as slush produces crystallisation. Without a trustworthy reading the module takes the conservative route and suspends dosing, which starts the legally mandated inducement sequence even though nothing mechanical is wrong. A fault here is consequently much more serious in January than in July, and worth reporting with the season attached. Note that a reading stuck cold has two explanations that look identical on a winter morning: a failed sensor, or a tank heater that genuinely is not working.

Also known as: adblue temperature sensor, def temp sensor, urea temperature sensor, reductant temp sensor

Referenced by 29 codes

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Codes involving this component (29)

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