General Outside temp sensor
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General Outside temp sensor
Bernievarian
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How it works:
the outside temperature sensor is built on the votage divider princip: two resistors in serie, one with fixed value and the other with negative temperature coefficient (NTC). A known voltage is applied on that bridge (at the ends) and the voltage at the junction point is measured to read the value of the variable element.
Let's assume both resistors have the same value (10K) and the voltage is 12V: the reading would be exactly half of the reference voltage [10/(10+10)*12= 6V]. Now if the NTC changes to 8K, the ratio between both resistors changes accordingly and the reading would be 8/18=0,444*12=5,33V.
Your reading of -33° seems to indicate either a short or an open circuit; MOST probably in the junction (D031) at the door hinge...
BRs, Bernie
If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
the outside temperature sensor is built on the votage divider princip: two resistors in serie, one with fixed value and the other with negative temperature coefficient (NTC). A known voltage is applied on that bridge (at the ends) and the voltage at the junction point is measured to read the value of the variable element.
Let's assume both resistors have the same value (10K) and the voltage is 12V: the reading would be exactly half of the reference voltage [10/(10+10)*12= 6V]. Now if the NTC changes to 8K, the ratio between both resistors changes accordingly and the reading would be 8/18=0,444*12=5,33V.
Your reading of -33° seems to indicate either a short or an open circuit; MOST probably in the junction (D031) at the door hinge...
BRs, Bernie
If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
