97 tracker ac/blower just quit

[pigmelt]

the ac and blower were working fine. except the blower only worked on hi speed. now neither work at all, checked the fuses at the kicker plate beside the left door floorboard and under the hood, all were good. is teher any other fuses or relays to check. i,m not to good with tools so any help or push in the right direction is helpful. thanks. btw i have had this 2 door soft top for about 1 yr the blower has only worked in hi speed the whole time.

[jtgh]

my guess:
the heater resistor network module is bad.

it has 3 huge resistors, for the multispeed fan.
and
my my schematic shows fan speed switch by passes
all resistors on HIGH, so bad switch for fan.

hope that helps.
and as always , it could be the wires or connectors bad. or even the fan , (hope not)

[pigmelt]

Originally Posted by jtgh

my guess:
the heater resistor network module is bad.

it has 3 huge resistors, for the multispeed fan.
and
my my schematic shows fan speed switch by passes
all resistors on HIGH, so bad switch for fan.

hope that helps.
and as always , it could be the wires or connectors bad. or even the fan , (hope not)

thanks will check it out. also atfer reading some of the posts in the archives that the ac presureswitch could cause the same thing is that possable?

[jtgh]

i cant imagine why.
if ac pressure drops, ECU will kill the Compresor clutch ,saving the
destruction of said compressor. "
shutting off a fan is not rational as IT is a safety device.
imagine fog/frost on windows. would you want that defeated?

nope.
imagine all the law suits.?

[pigmelt]

ok thanks i'm getting ready for work dont have a lot of time to check it to day so it will have to wait for a day off. i did not think of that. but waht would cause the ac to go out too, at the same time?

[jtgh]

not sure this car.
on many cars, the AC will not run if fan is not rotating.
"smart" when you think of of that. why waste energy if they heat exhangers is INOP. very smart.
how ever it ,might just be the bad switch being detected by the ECU.
Id take it one problem at a time.
fix fan, check AC freon for proper pressures, then try it.

[blondedriver]

I can see the fan needing to be running for the ac compressor clutch to be energized. On my old Ford Van the resistors went out, lost one of the sppeds then kept in a donimo effect

[jtgh]

if fan is off , core can freeze and then you get no defrost,
non to safe , so ECU commands off the Compresser clutch. Fix the fan. you will be amazed.

[pigmelt]

Originally Posted by jtgh

my guess:
the heater resistor network module is bad.

it has 3 huge resistors, for the multispeed fan.
and
my my schematic shows fan speed switch by passes
all resistors on HIGH, so bad switch for fan.

hope that helps.
and as always , it could be the wires or connectors bad. or even the fan , (hope not)

where can i find the resestors, and how do i get the fan switch out of the dash, i have removed the anti-theft ring but the switch is stubern to get out. thanks

[jtgh]

i do not have 97 fsm. so no instructions. sorry.

looking at EPC, i see assembly with 3 cables.
clamps and screws.
there is a Fan switch cable there.

the resistors are in module bolted on the top front of
the blower cage, the blower also cools the resistors .

I bet the switch is bad and the resistors are good.


It could be a bad motor too. ( chick this first)
see if there is power to the motor or hot wire it.
once side is ground, other side goes to blower switch and to the 4 range resistor bank.

hope I have helped.