change the blower motor the bearings have gone bad in it
The blower motor resistor on a 2005 Mercury Sable is typically located under the dashboard on the passenger side of the vehicle. It is usually mounted to the HVAC housing, near the blower motor itself. To access it, you may need to remove the lower dashboard panel or glove compartment for better visibility and access.
Look behind the glove box. under dash.
maybe your blower motor relay is stuck or burned together ???
A bad heater blower motor resistor would effect one or more blower speeds other than high.
The blower motor on a 1996 Mercury Sable is located under the dashboard on the passenger side. To access it, you typically need to remove the glove compartment and possibly some panels to reach the motor, which is mounted near the heater core. Make sure to disconnect the battery before attempting any repairs for safety.
The Mercury Cougar blower motor is located on the firewall in the engine compartment. The blower motor can be seen on the passenger side of the firewall.
Under dash at RH side, mounted with 3 bolts. R&I about 3 minutes.
If your blower is working on some speeds but not all, more than likely the problem is a defective Blower Motor Resistor Pack. The switch rarely goes bad. Just a thought.
Without knowing what model year the questioner is referring to...Budget somewhere around $35-60 for a blower motor - likely to be closer to the lower endSee "Related Questions" below for more
location of relay blower motor 1997 Mercury mystique
No repairing those blower motors, replace it with a new one.
front of the motor