I replaced the motor on my 2003 leSabre Limited.
To further diagnose if it's the blower motor itself that's having trouble probably with brush contact
on the commutator, when it does NOT work, keep the key ON and the blower motor speed selected on
the dash. Put your toe of your shoe up under the dash on the passenger side where the passenger's
left foot would rest. Tap on the bottom of the blower motor. If the fan starts working, the vibration
has helped the brushes make contact again.
And your car may have the blower filter access lid on the cowl, under the windshield wiper area.
You may be able to reach in, with the key ON at RUN and using something to reach turn the blower wheel.
That may start the blower. That would tell you it's the blower motor.
There's a slight possibility that the connector at the blower has bad metal contacts inside. The
corroded contact will heat due to the high current at times, soften the plastic holding it, and
that causes intermittent contact to occur. Tapping on the blower can cause that metal
contact to correct.
Look up under the passenger dash. You'll see the 3 wires plugged into the blower. Follow them
to the blower control module. That is your electronic "resistor." You may have to take off a
thin plastic panel under the dash. I May have taken off the door for the glovebox by undoing
the hinge screws underneath. I recall moving the interior of the blovebox and unsnapping a bulb
and a switch for the trunk security lock.
Be careful of any videos. There was a change in the blower setup in 2003. The blower motor
can be replaced by removing the 3 screws holding it into the larger housing. I found a video
that showed disassembling a lot of the car around the dash and then taking out the 5 screws that
hold the whole motor housing and I believe that was for the 2000-2002 models.
I did have to turn back the carpet to get room for the blower motor and squirrel cage to pivot
down and out. It is heavy. Be prepared to have a thick towel or something to help you support
your hand when you go to push the new one up into position, and then hold it while
you get all 3 screws in.
Best of luck. I recall lying on my side on the passenger floor with my worklight in the car and my
tools. It's doable.