Tom R

I already tested the fan & relay, they both are OK. I switched out the
Coolant Temperature Sensor today and still no luck.

Now I am wondering now if it could be the thermostat. I know the CTS is in
the same housing as the thermostat, but is it upstream of the thermostat?

Tom R.

"Snow" <snowball_2004@msn.com> wrote in message
news:848sc.9996$sr3.117197@news20.bellglobal.com.. .
> Well assuming its the same layout as my 4.0 , the electric fan gets its
> signal from the temp sensor on the thermostat housing, the gauge gets its
> signal from a sending unit on the after left hand side of the engine. the
> gauge and fan don't share the sensor/sending units. Sounds to me like
> either your temp sensor (on the t-stat housing) or the relay for it has
bit
> the dust. Eliminate the fan by connecting it directly to the battery, if
it
> spins then you know its good.
>
> Snow... "Don Cherry for Prime Minister"
>
>
> "Tom R" <tomr@noreply.com> wrote in message
> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
a
> > slow death (decreasing RPM's) so I recently replaced.
> >
> > The new fan worked fine for several days then it ran constantly after
the
> > engine was shut off. For several days I just unplugged the fan so it
would
> > not drain my battery. Now when I plug it back in, it does not work at
all,
> > even when the temperature guage reads 210+.
> >
> > The temperature guage, thermostat and relay appear to working correctly.
> >
> > Does the electric fan take its signal from the temperature sensor at the
> > thermostat or is there another sensor that could be causing the problem?
> >
> > Any suggestions?
> >
> > - Tom R
> >
> >
> >
>
>

Tom R

I already tested the fan & relay, they both are OK. I switched out the
Coolant Temperature Sensor today and still no luck.

Now I am wondering now if it could be the thermostat. I know the CTS is in
the same housing as the thermostat, but is it upstream of the thermostat?

Tom R.

"Snow" <snowball_2004@msn.com> wrote in message
news:848sc.9996$sr3.117197@news20.bellglobal.com.. .
> Well assuming its the same layout as my 4.0 , the electric fan gets its
> signal from the temp sensor on the thermostat housing, the gauge gets its
> signal from a sending unit on the after left hand side of the engine. the
> gauge and fan don't share the sensor/sending units. Sounds to me like
> either your temp sensor (on the t-stat housing) or the relay for it has
bit
> the dust. Eliminate the fan by connecting it directly to the battery, if
it
> spins then you know its good.
>
> Snow... "Don Cherry for Prime Minister"
>
>
> "Tom R" <tomr@noreply.com> wrote in message
> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
a
> > slow death (decreasing RPM's) so I recently replaced.
> >
> > The new fan worked fine for several days then it ran constantly after
the
> > engine was shut off. For several days I just unplugged the fan so it
would
> > not drain my battery. Now when I plug it back in, it does not work at
all,
> > even when the temperature guage reads 210+.
> >
> > The temperature guage, thermostat and relay appear to working correctly.
> >
> > Does the electric fan take its signal from the temperature sensor at the
> > thermostat or is there another sensor that could be causing the problem?
> >
> > Any suggestions?
> >
> > - Tom R
> >
> >
> >
>
>

Tom R

I already tested the fan & relay, they both are OK. I switched out the
Coolant Temperature Sensor today and still no luck.

Now I am wondering now if it could be the thermostat. I know the CTS is in
the same housing as the thermostat, but is it upstream of the thermostat?

Tom R.

"Snow" <snowball_2004@msn.com> wrote in message
news:848sc.9996$sr3.117197@news20.bellglobal.com.. .
> Well assuming its the same layout as my 4.0 , the electric fan gets its
> signal from the temp sensor on the thermostat housing, the gauge gets its
> signal from a sending unit on the after left hand side of the engine. the
> gauge and fan don't share the sensor/sending units. Sounds to me like
> either your temp sensor (on the t-stat housing) or the relay for it has
bit
> the dust. Eliminate the fan by connecting it directly to the battery, if
it
> spins then you know its good.
>
> Snow... "Don Cherry for Prime Minister"
>
>
> "Tom R" <tomr@noreply.com> wrote in message
> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
a
> > slow death (decreasing RPM's) so I recently replaced.
> >
> > The new fan worked fine for several days then it ran constantly after
the
> > engine was shut off. For several days I just unplugged the fan so it
would
> > not drain my battery. Now when I plug it back in, it does not work at
all,
> > even when the temperature guage reads 210+.
> >
> > The temperature guage, thermostat and relay appear to working correctly.
> >
> > Does the electric fan take its signal from the temperature sensor at the
> > thermostat or is there another sensor that could be causing the problem?
> >
> > Any suggestions?
> >
> > - Tom R
> >
> >
> >
>
>

bllsht

In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>, "Tom R"
wrote:

>I already tested the fan & relay, they both are OK. I switched out the
>Coolant Temperature Sensor today and still no luck.

The fan staying on before total failure sure sounds like a relay problem to me.
How did you test it?

If the old fan motor was so worn that it was running slow, it probably smoked
the relay.

>
>Now I am wondering now if it could be the thermostat. I know the CTS is in
>the same housing as the thermostat, but is it upstream of the thermostat?
>
>Tom R.
>
>"Snow" <snowball_2004@msn.com> wrote in message
>news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
>> Well assuming its the same layout as my 4.0 , the electric fan gets its
>> signal from the temp sensor on the thermostat housing, the gauge gets its
>> signal from a sending unit on the after left hand side of the engine. the
>> gauge and fan don't share the sensor/sending units. Sounds to me like
>> either your temp sensor (on the t-stat housing) or the relay for it has
>bit
>> the dust. Eliminate the fan by connecting it directly to the battery, if
>it
>> spins then you know its good.
>>
>> Snow... "Don Cherry for Prime Minister"
>>
>>
>> "Tom R" <tomr@noreply.com> wrote in message
>> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
>> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
>a
>> > slow death (decreasing RPM's) so I recently replaced.
>> >
>> > The new fan worked fine for several days then it ran constantly after
>the
>> > engine was shut off. For several days I just unplugged the fan so it
>would
>> > not drain my battery. Now when I plug it back in, it does not work at
>all,
>> > even when the temperature guage reads 210+.
>> >
>> > The temperature guage, thermostat and relay appear to working correctly.
>> >
>> > Does the electric fan take its signal from the temperature sensor at the
>> > thermostat or is there another sensor that could be causing the problem?
>> >
>> > Any suggestions?
>> >
>> > - Tom R
>> >
>> >
>> >
>>
>>
>
>

bllsht

In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>, "Tom R"
wrote:

>I already tested the fan & relay, they both are OK. I switched out the
>Coolant Temperature Sensor today and still no luck.

The fan staying on before total failure sure sounds like a relay problem to me.
How did you test it?

If the old fan motor was so worn that it was running slow, it probably smoked
the relay.

>
>Now I am wondering now if it could be the thermostat. I know the CTS is in
>the same housing as the thermostat, but is it upstream of the thermostat?
>
>Tom R.
>
>"Snow" <snowball_2004@msn.com> wrote in message
>news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
>> Well assuming its the same layout as my 4.0 , the electric fan gets its
>> signal from the temp sensor on the thermostat housing, the gauge gets its
>> signal from a sending unit on the after left hand side of the engine. the
>> gauge and fan don't share the sensor/sending units. Sounds to me like
>> either your temp sensor (on the t-stat housing) or the relay for it has
>bit
>> the dust. Eliminate the fan by connecting it directly to the battery, if
>it
>> spins then you know its good.
>>
>> Snow... "Don Cherry for Prime Minister"
>>
>>
>> "Tom R" <tomr@noreply.com> wrote in message
>> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
>> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
>a
>> > slow death (decreasing RPM's) so I recently replaced.
>> >
>> > The new fan worked fine for several days then it ran constantly after
>the
>> > engine was shut off. For several days I just unplugged the fan so it
>would
>> > not drain my battery. Now when I plug it back in, it does not work at
>all,
>> > even when the temperature guage reads 210+.
>> >
>> > The temperature guage, thermostat and relay appear to working correctly.
>> >
>> > Does the electric fan take its signal from the temperature sensor at the
>> > thermostat or is there another sensor that could be causing the problem?
>> >
>> > Any suggestions?
>> >
>> > - Tom R
>> >
>> >
>> >
>>
>>
>
>

bllsht

In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>, "Tom R"
wrote:

>I already tested the fan & relay, they both are OK. I switched out the
>Coolant Temperature Sensor today and still no luck.

The fan staying on before total failure sure sounds like a relay problem to me.
How did you test it?

If the old fan motor was so worn that it was running slow, it probably smoked
the relay.

>
>Now I am wondering now if it could be the thermostat. I know the CTS is in
>the same housing as the thermostat, but is it upstream of the thermostat?
>
>Tom R.
>
>"Snow" <snowball_2004@msn.com> wrote in message
>news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
>> Well assuming its the same layout as my 4.0 , the electric fan gets its
>> signal from the temp sensor on the thermostat housing, the gauge gets its
>> signal from a sending unit on the after left hand side of the engine. the
>> gauge and fan don't share the sensor/sending units. Sounds to me like
>> either your temp sensor (on the t-stat housing) or the relay for it has
>bit
>> the dust. Eliminate the fan by connecting it directly to the battery, if
>it
>> spins then you know its good.
>>
>> Snow... "Don Cherry for Prime Minister"
>>
>>
>> "Tom R" <tomr@noreply.com> wrote in message
>> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
>> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
>a
>> > slow death (decreasing RPM's) so I recently replaced.
>> >
>> > The new fan worked fine for several days then it ran constantly after
>the
>> > engine was shut off. For several days I just unplugged the fan so it
>would
>> > not drain my battery. Now when I plug it back in, it does not work at
>all,
>> > even when the temperature guage reads 210+.
>> >
>> > The temperature guage, thermostat and relay appear to working correctly.
>> >
>> > Does the electric fan take its signal from the temperature sensor at the
>> > thermostat or is there another sensor that could be causing the problem?
>> >
>> > Any suggestions?
>> >
>> > - Tom R
>> >
>> >
>> >
>>
>>
>
>

bllsht

In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>, "Tom R"
wrote:

>I already tested the fan & relay, they both are OK. I switched out the
>Coolant Temperature Sensor today and still no luck.

The fan staying on before total failure sure sounds like a relay problem to me.
How did you test it?

If the old fan motor was so worn that it was running slow, it probably smoked
the relay.

>
>Now I am wondering now if it could be the thermostat. I know the CTS is in
>the same housing as the thermostat, but is it upstream of the thermostat?
>
>Tom R.
>
>"Snow" <snowball_2004@msn.com> wrote in message
>news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
>> Well assuming its the same layout as my 4.0 , the electric fan gets its
>> signal from the temp sensor on the thermostat housing, the gauge gets its
>> signal from a sending unit on the after left hand side of the engine. the
>> gauge and fan don't share the sensor/sending units. Sounds to me like
>> either your temp sensor (on the t-stat housing) or the relay for it has
>bit
>> the dust. Eliminate the fan by connecting it directly to the battery, if
>it
>> spins then you know its good.
>>
>> Snow... "Don Cherry for Prime Minister"
>>
>>
>> "Tom R" <tomr@noreply.com> wrote in message
>> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
>> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going through
>a
>> > slow death (decreasing RPM's) so I recently replaced.
>> >
>> > The new fan worked fine for several days then it ran constantly after
>the
>> > engine was shut off. For several days I just unplugged the fan so it
>would
>> > not drain my battery. Now when I plug it back in, it does not work at
>all,
>> > even when the temperature guage reads 210+.
>> >
>> > The temperature guage, thermostat and relay appear to working correctly.
>> >
>> > Does the electric fan take its signal from the temperature sensor at the
>> > thermostat or is there another sensor that could be causing the problem?
>> >
>> > Any suggestions?
>> >
>> > - Tom R
>> >
>> >
>> >
>>
>>
>
>

Tom R

I switched the relay for the electric fan (40) with the ignition relay (also
40).


"bllsht" <nospam@invaliddot.net> wrote in message
news:29q5b09l80o8uit5gr9et3hr5fudnofp92@4ax.com...
> In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>,
"Tom R"
> wrote:
>
> >I already tested the fan & relay, they both are OK. I switched out the
> >Coolant Temperature Sensor today and still no luck.
>
> The fan staying on before total failure sure sounds like a relay problem
to me.
> How did you test it?
>
> If the old fan motor was so worn that it was running slow, it probably
smoked
> the relay.
>
> >
> >Now I am wondering now if it could be the thermostat. I know the CTS is
in
> >the same housing as the thermostat, but is it upstream of the thermostat?
> >
> >Tom R.
> >
> >"Snow" <snowball_2004@msn.com> wrote in message
> >news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
> >> Well assuming its the same layout as my 4.0 , the electric fan gets
its
> >> signal from the temp sensor on the thermostat housing, the gauge gets
its
> >> signal from a sending unit on the after left hand side of the engine.
the
> >> gauge and fan don't share the sensor/sending units. Sounds to me
like
> >> either your temp sensor (on the t-stat housing) or the relay for it has
> >bit
> >> the dust. Eliminate the fan by connecting it directly to the battery,
if
> >it
> >> spins then you know its good.
> >>
> >> Snow... "Don Cherry for Prime Minister"
> >>
> >>
> >> "Tom R" <tomr@noreply.com> wrote in message
> >> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> >> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going
through
> >a
> >> > slow death (decreasing RPM's) so I recently replaced.
> >> >
> >> > The new fan worked fine for several days then it ran constantly after
> >the
> >> > engine was shut off. For several days I just unplugged the fan so it
> >would
> >> > not drain my battery. Now when I plug it back in, it does not work at
> >all,
> >> > even when the temperature guage reads 210+.
> >> >
> >> > The temperature guage, thermostat and relay appear to working
correctly.
> >> >
> >> > Does the electric fan take its signal from the temperature sensor at
the
> >> > thermostat or is there another sensor that could be causing the
problem?
> >> >
> >> > Any suggestions?
> >> >
> >> > - Tom R
> >> >
> >> >
> >> >
> >>
> >>
> >
> >
>

Tom R

I switched the relay for the electric fan (40) with the ignition relay (also
40).


"bllsht" <nospam@invaliddot.net> wrote in message
news:29q5b09l80o8uit5gr9et3hr5fudnofp92@4ax.com...
> In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>,
"Tom R"
> wrote:
>
> >I already tested the fan & relay, they both are OK. I switched out the
> >Coolant Temperature Sensor today and still no luck.
>
> The fan staying on before total failure sure sounds like a relay problem
to me.
> How did you test it?
>
> If the old fan motor was so worn that it was running slow, it probably
smoked
> the relay.
>
> >
> >Now I am wondering now if it could be the thermostat. I know the CTS is
in
> >the same housing as the thermostat, but is it upstream of the thermostat?
> >
> >Tom R.
> >
> >"Snow" <snowball_2004@msn.com> wrote in message
> >news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
> >> Well assuming its the same layout as my 4.0 , the electric fan gets
its
> >> signal from the temp sensor on the thermostat housing, the gauge gets
its
> >> signal from a sending unit on the after left hand side of the engine.
the
> >> gauge and fan don't share the sensor/sending units. Sounds to me
like
> >> either your temp sensor (on the t-stat housing) or the relay for it has
> >bit
> >> the dust. Eliminate the fan by connecting it directly to the battery,
if
> >it
> >> spins then you know its good.
> >>
> >> Snow... "Don Cherry for Prime Minister"
> >>
> >>
> >> "Tom R" <tomr@noreply.com> wrote in message
> >> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> >> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going
through
> >a
> >> > slow death (decreasing RPM's) so I recently replaced.
> >> >
> >> > The new fan worked fine for several days then it ran constantly after
> >the
> >> > engine was shut off. For several days I just unplugged the fan so it
> >would
> >> > not drain my battery. Now when I plug it back in, it does not work at
> >all,
> >> > even when the temperature guage reads 210+.
> >> >
> >> > The temperature guage, thermostat and relay appear to working
correctly.
> >> >
> >> > Does the electric fan take its signal from the temperature sensor at
the
> >> > thermostat or is there another sensor that could be causing the
problem?
> >> >
> >> > Any suggestions?
> >> >
> >> > - Tom R
> >> >
> >> >
> >> >
> >>
> >>
> >
> >
>

Tom R

I switched the relay for the electric fan (40) with the ignition relay (also
40).


"bllsht" <nospam@invaliddot.net> wrote in message
news:29q5b09l80o8uit5gr9et3hr5fudnofp92@4ax.com...
> In message <Gctsc.24027$fF3.612160@bgtnsc05-news.ops.worldnet.att.net>,
"Tom R"
> wrote:
>
> >I already tested the fan & relay, they both are OK. I switched out the
> >Coolant Temperature Sensor today and still no luck.
>
> The fan staying on before total failure sure sounds like a relay problem
to me.
> How did you test it?
>
> If the old fan motor was so worn that it was running slow, it probably
smoked
> the relay.
>
> >
> >Now I am wondering now if it could be the thermostat. I know the CTS is
in
> >the same housing as the thermostat, but is it upstream of the thermostat?
> >
> >Tom R.
> >
> >"Snow" <snowball_2004@msn.com> wrote in message
> >news:848sc.9996$sr3.117197@news20.bellglobal.com. ..
> >> Well assuming its the same layout as my 4.0 , the electric fan gets
its
> >> signal from the temp sensor on the thermostat housing, the gauge gets
its
> >> signal from a sending unit on the after left hand side of the engine.
the
> >> gauge and fan don't share the sensor/sending units. Sounds to me
like
> >> either your temp sensor (on the t-stat housing) or the relay for it has
> >bit
> >> the dust. Eliminate the fan by connecting it directly to the battery,
if
> >it
> >> spins then you know its good.
> >>
> >> Snow... "Don Cherry for Prime Minister"
> >>
> >>
> >> "Tom R" <tomr@noreply.com> wrote in message
> >> news:ec6sc.19789$fF3.505534@bgtnsc05-news.ops.worldnet.att.net...
> >> > 1999 Grand Cherokee w/ 4.0L. The electric cooling fan was going
through
> >a
> >> > slow death (decreasing RPM's) so I recently replaced.
> >> >
> >> > The new fan worked fine for several days then it ran constantly after
> >the
> >> > engine was shut off. For several days I just unplugged the fan so it
> >would
> >> > not drain my battery. Now when I plug it back in, it does not work at
> >all,
> >> > even when the temperature guage reads 210+.
> >> >
> >> > The temperature guage, thermostat and relay appear to working
correctly.
> >> >
> >> > Does the electric fan take its signal from the temperature sensor at
the
> >> > thermostat or is there another sensor that could be causing the
problem?
> >> >
> >> > Any suggestions?
> >> >
> >> > - Tom R
> >> >
> >> >
> >> >
> >>
> >>
> >
> >
>