Dead AC/heater blower, 2000 Cherokee
 

Hello all, I have a 2000 Cherokee. My heater/AC blower won't turn on. I
had a dead battery and a blown fused wire (idiot with a jump pack). A
battery shop replaced the battery and wire but I picked it up after
hours and when I tried to turn on the heat - no fan. The radio was dead
too, I fixed that by replacing a blown fuse. The shop is pretty much no
help and two hours away, all they say is "bring it in", yeah right,
drive four hours for a $10 part).

The fuse marked "blower" 40AMP, in the power distribution center is
fine. A friend suggested it may be a relay, the question is which one
and where and how would I test it (I have a multimeter, just no idea
how to test a relay). I realize I could also have a fried wire
somewhere but hoping for the relay. Any other thoughts?

Thanks,

Aaron

http://www.billhughes.com/blower.pdf
God Bless America, ßill O|||||||O


wrote:
>
> Hello all, I have a 2000 Cherokee. My heater/AC blower won't turn on. I
> had a dead battery and a blown fused wire (idiot with a jump pack). A
> battery shop replaced the battery and wire but I picked it up after
> hours and when I tried to turn on the heat - no fan. The radio was dead
> too, I fixed that by replacing a blown fuse. The shop is pretty much no
> help and two hours away, all they say is "bring it in", yeah right,
> drive four hours for a $10 part).
>
> The fuse marked "blower" 40AMP, in the power distribution center is
> fine. A friend suggested it may be a relay, the question is which one
> and where and how would I test it (I have a multimeter, just no idea
> how to test a relay). I realize I could also have a fried wire
> somewhere but hoping for the relay. Any other thoughts?
>
> Thanks,
>
> Aaron

look inthe owners manual and you will find other fuses under the dash
it's best to use a test lite to test the fuses a hiarline crack in the fuse
may not be seen

wrote:

> Hello all, I have a 2000 Cherokee. My heater/AC blower won't turn on. I
> had a dead battery and a blown fused wire (idiot with a jump pack). A
> battery shop replaced the battery and wire but I picked it up after
> hours and when I tried to turn on the heat - no fan. The radio was dead
> too, I fixed that by replacing a blown fuse. The shop is pretty much no
> help and two hours away, all they say is "bring it in", yeah right,
> drive four hours for a $10 part).
>
> The fuse marked "blower" 40AMP, in the power distribution center is
> fine. A friend suggested it may be a relay, the question is which one
> and where and how would I test it (I have a multimeter, just no idea
> how to test a relay). I realize I could also have a fried wire
> somewhere but hoping for the relay. Any other thoughts?
>
> Thanks,
>
> Aaron

L=2EW. Hughes III (=DFill) wrote:
> http://www.billhughes.com/blower.pdf

Thanks, just what I needed. The relay was indeed blown with some
visible scorching on 87 and 87a. Unfortunatly replacing the relay did
not fix the problem. I tried the "relay circuit test" as outlined in
the manual above but am a bit confused. It says there should be voltage
to cavity 30 at all times, there is not. There is voltage to cavity 87
which the guide seems to say there should not be. Do I have a fried
wire here?

Thanks,

Aaron

wrote:
> L.W. Hughes III (=DFill) wrote:
> > http://www.billhughes.com/blower.pdf
>
I'm getting closer to getting this thing fixed.

The blower itself works fine if I put a jumper across the main relay
cavities. The relay itself tests out OK.

I found a blown 15A fuse, #25, in the fuse block. I replaced it but it
blows as soon as the ignition is turned on. When I put a jumper across
it the relay energized (I heard it click) and the blower worked
properly.

Anyone know why this fuse would keep blowing out?

Thanks,

Aaron

did pass the time by typing:
> wrote:
>> L.W. Hughes III (ßill) wrote:
>>> http://www.billhughes.com/blower.pdf
>>
> I'm getting closer to getting this thing fixed.
>
> The blower itself works fine if I put a jumper across the main relay
> cavities. The relay itself tests out OK.
>
> I found a blown 15A fuse, #25, in the fuse block. I replaced it but it
> blows as soon as the ignition is turned on. When I put a jumper across
> it the relay energized (I heard it click) and the blower worked
> properly.
>
> Anyone know why this fuse would keep blowing out?

Fuses blow to prevent the wires from melting and catching fire.

So, that means something down the line is pulling way too much
current. That can be a motor that has shorted windings. Motors
that fail this way still work but they draw a lot of current.

Disconnect the motor, put in a new fuse, and try again. If it
doesn't blow it's the motor. If it blows then I dunno, need a
schematic to help you any further.

--
DougW

Ditto.
God Bless America, ßill O|||||||O
http://www.billhughes.com/

DougW wrote:
>
> Fuses blow to prevent the wires from melting and catching fire.
>
> So, that means something down the line is pulling way too much
> current. That can be a motor that has shorted windings. Motors
> that fail this way still work but they draw a lot of current.
>
> Disconnect the motor, put in a new fuse, and try again. If it
> doesn't blow it's the motor. If it blows then I dunno, need a
> schematic to help you any further.
>
> --
> DougW

a short what is the position number for the fuse

wrote:

> wrote:
> > L.W. Hughes III (ßill) wrote:
> > > http://www.billhughes.com/blower.pdf
> >
> I'm getting closer to getting this thing fixed.
>
> The blower itself works fine if I put a jumper across the main relay
> cavities. The relay itself tests out OK.
>
> I found a blown 15A fuse, #25, in the fuse block. I replaced it but it
> blows as soon as the ignition is turned on. When I put a jumper across
> it the relay energized (I heard it click) and the blower worked
> properly.
>
> Anyone know why this fuse would keep blowing out?
>
> Thanks,
>
> Aaron

i just checked in a manual the 25 fuse is for the factory amp for the radio
it has no connectiopn to the hvac of the jeep
do u have one and does it work and do u have a aftermarket radio in the
jeep???

DougW wrote:

> did pass the time by typing:
> > wrote:
> >> L.W. Hughes III (ßill) wrote:
> >>> http://www.billhughes.com/blower.pdf
> >>
> > I'm getting closer to getting this thing fixed.
> >
> > The blower itself works fine if I put a jumper across the main relay
> > cavities. The relay itself tests out OK.
> >
> > I found a blown 15A fuse, #25, in the fuse block. I replaced it but it
> > blows as soon as the ignition is turned on. When I put a jumper across
> > it the relay energized (I heard it click) and the blower worked
> > properly.
> >
> > Anyone know why this fuse would keep blowing out?
>
> Fuses blow to prevent the wires from melting and catching fire.
>
> So, that means something down the line is pulling way too much
> current. That can be a motor that has shorted windings. Motors
> that fail this way still work but they draw a lot of current.
>
> Disconnect the motor, put in a new fuse, and try again. If it
> doesn't blow it's the motor. If it blows then I dunno, need a
> schematic to help you any further.
>
> --
> DougW

tim bur wrote:
> a short what is the position number for the fuse
>
#25, right above the two airbag fuses (only 2 that are labeled - Yes, I
know there should be a label on the panel cover but there is not).

Thanks,

Aaron