please explain this to me

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rburgy
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please explain this to me

Post by rburgy » Thu Jan 15, 2015 12:35 am

When a low or high voltage code is logged. why is a short considered a low voltage code and an open or high resistance a high voltage code. take a coolant temp sensor for example; if the 5 volt reference and the return are shorted together, I would think that was a high voltage code because you have all 5v coming back on return side all the time. its not- its a low voltage code. and the other way around, if the return line is open its considered a high voltage code, but you would think it would be a low voltage code because nothing is coming back.
that's how I see it, but can anyone explain to me why it is opposite???
thanks al;l

edagrade
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Re: please explain this to me

Post by edagrade » Thu Jan 15, 2015 1:10 am

A short to ground will pull the voltage low... hence low voltage code.

An open will leave the voltage potential high... hence high voltage code.

rburgy
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Re: please explain this to me

Post by rburgy » Thu Jan 15, 2015 11:18 am

Thank you for the explaination.

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