Yes.
the air gets thinner.
The liquid which turn in to gel once PH or temp change
You cant.
These are phase changes - All the energy that is added at this time is used to change the phase of the substance.
Hold down the lower TEMP button together with the ABM button for 5 seconds.
it has many temp because it can be changed by a reaction of the change in temp
Don't know if this works in a 99' but I have a 97'. You have reset the "oil life remaining" readout and this will reset "change oil" indicator. Scroll thru your various readouts (rpm's, water temp, battery volts, etc.) till you see it and then just press reset. Hope this works for you.
SENSOR DISCONNECTED?
May be located in the head nearest the firewall on the driver's side. That's where it is on my 95 3100.
It sounds like you have two separate problems. Incorrect routing of ventilation is usually caused by bad vacuum motors or loose vacuum lines, but remember that A/C is -supposed to be- routed to the defrost vents when controls are in the Defrost position. The dim temp control readout could be due to a number of causes, but probably isn't related to the other issue you describe.
i change the thermostat and the temp switch but still not working
Change in temp=final temp-initial temp, so -5-15=-20 lrn to math
You need to let us know if it has a digital readout, or if it has the traditional mechanical odometer.
Just changing the oil doesn't do anything to the gauge, hold reset button down until readout changes change the oil
The Ambient Temperature Sensor is located behind the grill and mounted to the radiator support with a "push in" connector. Remove the screws that attach the upper portion of the grill and pull the grill away from the vehicle enough to access the sensor.
A salamander is a cold blooded animal. So it simply follows the temperature change. Temperature goes down, its body temp goes down, Temp goes up its body temp goes up