cars that are equipped with ac are supposed to run when the heat selection is on : max a/c , a/c , mix or defrost. the ac pump dries the air that flows through it which helps to clear the windshield and also to help to feel cooler in the summer . i have pulled the plug on the compressor before to turn it off during the winter months but it is just fine to run
Also, heat settings keep the compressor running to prevent it from seizing. The number 1 cause of compressor failure was due to lack of use during the long winter months.
The switch located on the door frame may be broken is a dome light stays on in a Mercury Sable. The switch may need to be repaired. If that is not the issue, a mechanic can diagnose the issue. Another way to help find a solution is to look in the owner manual or repair book for the car.
chances are that you have a blockage somewhere heater core radiator heater hose try flushing the system first then go from there
On a 2001 Mercury Sable : That's your " CHECK TRANSAXLE " ( transmission ) warning light The warning light is located in the bottom of the tachometer on the left side . If the light stays on take the vehicle in for servicing
replace the heater temperature switch
it could be a relay. it is located in your fuses box. it might need to be replaced or you might just need to blow it off.
This question was for a 1998 Mazda 626. The solution to this problem of the temp heating up is to start the heater in the car on high. Then it immediately goes to the neutral temp for the car, and stays in stable there.
It stays on UNLESS you have a commercial heater with an electronic ignition
According to the 2000 Mercury Sable owners manual : That's your check transaxle warning light ( located in the bottom / left of the tachometer ) A problem has been detected , shifting may be restricted ( if the warning light stays on , have your vehicle serviced immediately )
When it's broken or the mercury stays the same.
because it a liquid and it stays at room temoture
Have the codes read.