My heat worked fine last night an today i start the car an the heat box is digital it say the heat is on but it pushs out nothing just alil cold air so i turn it on hi an it does nothing i dunno where the relay is located i can't find a diagram of anything not even my fuse box's they have no covers, this is for a toyota supra 1986 turbo plz help hurry or just tell me where the heat relay is

If the digital box is on, Your fuse and relay are ok, first check your heater core houses both had to have the same temperature, engines temperature, one of them has a valve with an internal door every time you press th e heat in you digital climate control, this valve move allowing hot coolant recirculate across your heater core then the blower give you heat, if this valve don't move then there is two reasons, valve stuck, or bad actuator, what you got to do is gently disconnect the cable from the valve and see if the valve move with your fingers , move it in opposite directions and in every try go inside the car and see if you have heat if you do the problem is inside the car climate control box or actuator, or broken cable.

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