if the press the awd button on my 2009 santa fe it it engaged when its says awd locked
Your Santa fe is a part time awd. Which means when the front tires slip the rear will then engage. Like if it just started snowing or the roads are clear but the snow is drifting. If you push the lock button its for bad weather where there is a few inches of snow on the ground already. Your fuel mileage is much better with it off.
YES, when you engage the switch and the light comes on, your car is now in all wheel drive all the time, until you disengage it with the switch, or turn the car off then restart it.
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