A common problem with 2002 LS's are the DCCV, (Dual Climate Control Valve). Pretty expensive, so I suggest finding someone who know's how to reset the climate control and see if that helps. Other than that, you might need to check the DCCV. Also, a no-brainer, make sure your R-134a is topped off. Hope this helps.
bad blower switch located behind blower control.
BLOWER MOTOR RESITAR SWITCH
Blower motor NG. Blower motor resister NG. Blower motor fuse NG. Blower motor switch NG.
On the firewall to the right (when facing the firewall) of the blower motor.
The blower on a 2002 Nissan Pathfinder won't turn off if the switch is stuck in the on position or the relay is defective. Removing the blower fuse will cause the fan to turn off.
The fuse. The blower motor speed resistor. The blower motor relay. The blower motor switch. Check for power at the blower motor connection.
According to the 2002 Lincoln Navigator owners manual the on / off switch for the air suspension system is located in the front passenger footwell
Typically a relay or resistor. But could be a blower switch or blower motor problem.
It could be the blower motor, control switch, relay (if your vehicle uses one), loose connection or bad fuse.
Check the blower motors ground and power in the truck and the blower motors resister......
check the fuse, the relay, the switch and the blower motor resister. If these all check out could be the blower motor its self is faulty
Try replacing blower control switch or module.