The problem is probably the common blend door failure on the Explorer. Follow my user name to my Bio page for a pointer to the HeaterTreater web site. The site has diagnostic information on the problem and a bullet proof fix. ford4me
bulbs or bulb sockets
Itmight be the model of your car. My dad knows.
At your own risks. I had a similar problem with my 1996 Explorer Eddie Bauer...Unfortunately, I replaced the transmission as a unit and later on found out that a faulty TPS sensor may cause the transmission to disengage. I would suggest a process of elimination by starting with the small item first which in this cars may be the TPS sensor. JB
It is possible the blower motor fan is starting to seize up or is loose and catching on inside fan housing.
The blend door is on a vertical axis in the Explorer and it sounds like when you set the fan to high, you are blowing the door to a position where the heater core is open. The root cause of the problem is a broken blend door. Once the door breaks, it "blows in the breeze" and there are different combinations of turning corners hard, hitting bumps, changing fan speed, switching mode, etc. that will get temporary heat. The blend door has to be replaced to regain control of the system. This is a common failure on the Explorer and is an expensive fix at the dealer. Follow my user name to my Bio Page for a pointer to the HeaterTreater web site. This site has diagnostic information on this particular problem and an inexpensive fix. ford4me
It could be the idle control P1507
I had the same problem on a 2001 Ford Explorer Eddie Bauer. I took it to the Ford dealer and it ended up being caused by a faulty throttle body sensor. Dont know the exact details of the repair but look toward the throttle body being the cause. After they fixed it, I haven't had any trouble since.
Most likely a bad coil (each cylinder has one) located at the top of each spark plug
The most common cause of the heater blower being on high only is the blower resister failing. The second most common problem is the blower switch going bad.
he cause discontent and unrest
For this answer you will need to either use an OBD code reader or go to a shop that can read codes. Also make sure that your air suspension switch is turned on.
Have you checked the guage panel dimmer wheel switch ( just to the right of your headlight switch on your dash ) to see if it has been rotated all the way down ? The dimmer wheel is used to adjust the backlighting brightness of your guages and also , if it is rotated all the way up , it turns on all your interior courtesy lights - Helpfull