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- - Voltage Issue (https://blazerforum.com/forum/lighting-electrical-52/voltage-issue-97995/)

Quote:

Originally Posted by Blazer112 (Post 697492)

Hello,
Any ideas why the connector to my map sensor reads 70 volts? The base line connection reads the nominal 5 Volts. I have randomly check other electrical points and they read 12 volts. I have a 2004 Blazer ZR 2 and have owned it since day 1. My Blazer started missing badly while cruising at 40mph and the check engine light and subsequent scan identified the faulty sensor. I changed it but the problem persists. Thank you for your time.

I don't even see how that's possible. The battery is only 12v. There is no voltage higher than that in the vehicle, except for the ignition, and that's probably over 20k volts.

Is it reading 70vac or DC?

So, that's the only place you're reading that high of a voltage? Sounds like you need to spend a day tracing out wiring and figuring out where it's coming from!

You would think if it was the alternator, everything would be high, not just that one circuit

Edit: even if it were possible to be induction, wouldn't that be AC? Can't really induce DC, can you?

Just to make sure, test you alternator and see if it is putting out any A/C voltage.
Many auto parts stores can bench test it for you for free.
https://www.knowyourparts.com/techni...-misdiagnosis/

I would think that in order for the alternator to put out AC voltage the rectifier would be bad, but you would see high voltage in basicly the whole rig. Very puzzling.