Toyota Highlander charging system acting strange
I put a voltmeter on a 2017 Highlander that I just bought. The readings don’t make any sense.
When it is idling in park, the voltage is 14.6V.
If I am idling in Drive, it is 12.4V. RPM ~ 700. If I give it a little gas to bring the RPMs back to 1000 it does not change back to 14.6V where it was in park.
When I am driving, the voltage is 12.4V. RPM can be anything.
If I take my foot off the gas pedal while I am driving, it goes back to 14.6V.
That can't be right.
I expect it to be in the 14V range while driving and possibly to decrease if the RPMs fell as in when I took my foot off the gas.
I have checked the belt and it is in good condition and tight. There is no noise that would indicate it is slipping.
Can anyone explain this to me, or is there a problem I can’t explain.
the answer is fuel economy.
When the engine is driving the vehicle, the alternator is cut out to allow all the power to go to the wheels.