(89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
about cooling fans (electric) and it got me to wondering. My fan works but
some times I notice it doesn't work. for instance, If I am sitting at a
drive up window or a long stop light etc... sometimes it over heats. that
is, until I put the transmission in park, then the fan kicks on. I have been
keeping a watch on it and sometimes it works normally and sometimes I have
to put it in park, then it comes on normally after that.

this sounds bizarre to me. am I nuts? is this possible?

I have AC, it works fine then, I have a brand new radiator and fresh
coolant.

 

I'll assume you have a 4.0 under the hood. Most likely your problem is with
the temp. switch that turns the electric fan on. Here's a couple easy
tests to do.
1) connect the fan directly to the battery, if the fan spins its good. (by
the sounds of it the fan is functioning)
2) I believe you said you have a/c. with the engine running select the
heater control to defrost, as soon as you do the electric fan should start
running. Next turn the heater off then turn it back on at one of the a/c
settings again the fan should run.

If the fan operates normally when you perform the above, I would say it is
the temp. switch. I'm not sure if my 93 is the same layout as yours but the
temp. switch on mine is located on the t-stat housing.

Snow...
"Richard" <rwrede2@hotmail.com> wrote in message
news:10ln5inj6sg3v44@corp.supernews.com...
> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
> about cooling fans (electric) and it got me to wondering. My fan works but
> some times I notice it doesn't work. for instance, If I am sitting at a
> drive up window or a long stop light etc... sometimes it over heats. that
> is, until I put the transmission in park, then the fan kicks on. I have
been
> keeping a watch on it and sometimes it works normally and sometimes I have
> to put it in park, then it comes on normally after that.
>
> this sounds bizarre to me. am I nuts? is this possible?
>
> I have AC, it works fine then, I have a brand new radiator and fresh
> coolant.
>
>

 

I'll assume you have a 4.0 under the hood. Most likely your problem is with
the temp. switch that turns the electric fan on. Here's a couple easy
tests to do.
1) connect the fan directly to the battery, if the fan spins its good. (by
the sounds of it the fan is functioning)
2) I believe you said you have a/c. with the engine running select the
heater control to defrost, as soon as you do the electric fan should start
running. Next turn the heater off then turn it back on at one of the a/c
settings again the fan should run.

If the fan operates normally when you perform the above, I would say it is
the temp. switch. I'm not sure if my 93 is the same layout as yours but the
temp. switch on mine is located on the t-stat housing.

Snow...
"Richard" <rwrede2@hotmail.com> wrote in message
news:10ln5inj6sg3v44@corp.supernews.com...
> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
> about cooling fans (electric) and it got me to wondering. My fan works but
> some times I notice it doesn't work. for instance, If I am sitting at a
> drive up window or a long stop light etc... sometimes it over heats. that
> is, until I put the transmission in park, then the fan kicks on. I have
been
> keeping a watch on it and sometimes it works normally and sometimes I have
> to put it in park, then it comes on normally after that.
>
> this sounds bizarre to me. am I nuts? is this possible?
>
> I have AC, it works fine then, I have a brand new radiator and fresh
> coolant.
>
>

 

I'll assume you have a 4.0 under the hood. Most likely your problem is with
the temp. switch that turns the electric fan on. Here's a couple easy
tests to do.
1) connect the fan directly to the battery, if the fan spins its good. (by
the sounds of it the fan is functioning)
2) I believe you said you have a/c. with the engine running select the
heater control to defrost, as soon as you do the electric fan should start
running. Next turn the heater off then turn it back on at one of the a/c
settings again the fan should run.

If the fan operates normally when you perform the above, I would say it is
the temp. switch. I'm not sure if my 93 is the same layout as yours but the
temp. switch on mine is located on the t-stat housing.

Snow...
"Richard" <rwrede2@hotmail.com> wrote in message
news:10ln5inj6sg3v44@corp.supernews.com...
> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
> about cooling fans (electric) and it got me to wondering. My fan works but
> some times I notice it doesn't work. for instance, If I am sitting at a
> drive up window or a long stop light etc... sometimes it over heats. that
> is, until I put the transmission in park, then the fan kicks on. I have
been
> keeping a watch on it and sometimes it works normally and sometimes I have
> to put it in park, then it comes on normally after that.
>
> this sounds bizarre to me. am I nuts? is this possible?
>
> I have AC, it works fine then, I have a brand new radiator and fresh
> coolant.
>
>

 

Your fan should come on automatically at around 210. Also it should always
be on whenever you turn on the air conditioning compressor (defrost AC etc).
There is a relay (square bosch style) on the drivers side fender wall in the
engine compartment roughly beside the air cleaner box. Your problem is
either the fan, the relay or the temp sender located in the radiator above
the transmission lines on the drivers side. (after 1991 they put the sender
in the thermostat elbow) My money is on your relay.
KH

"Snow" <snowball_2004@msn.com> wrote in message
news:HrS6d.18394$MD5.996517@news20.bellglobal.com. ..
> I'll assume you have a 4.0 under the hood. Most likely your problem is
> with
> the temp. switch that turns the electric fan on. Here's a couple easy
> tests to do.
> 1) connect the fan directly to the battery, if the fan spins its good.
> (by
> the sounds of it the fan is functioning)
> 2) I believe you said you have a/c. with the engine running select the
> heater control to defrost, as soon as you do the electric fan should start
> running. Next turn the heater off then turn it back on at one of the a/c
> settings again the fan should run.
>
> If the fan operates normally when you perform the above, I would say it is
> the temp. switch. I'm not sure if my 93 is the same layout as yours but
> the
> temp. switch on mine is located on the t-stat housing.
>
> Snow...
> "Richard" <rwrede2@hotmail.com> wrote in message
> news:10ln5inj6sg3v44@corp.supernews.com...
>> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
>> about cooling fans (electric) and it got me to wondering. My fan works
>> but
>> some times I notice it doesn't work. for instance, If I am sitting at a
>> drive up window or a long stop light etc... sometimes it over heats. that
>> is, until I put the transmission in park, then the fan kicks on. I have
> been
>> keeping a watch on it and sometimes it works normally and sometimes I
>> have
>> to put it in park, then it comes on normally after that.
>>
>> this sounds bizarre to me. am I nuts? is this possible?
>>
>> I have AC, it works fine then, I have a brand new radiator and fresh
>> coolant.
>>
>>
>
>

 

Your fan should come on automatically at around 210. Also it should always
be on whenever you turn on the air conditioning compressor (defrost AC etc).
There is a relay (square bosch style) on the drivers side fender wall in the
engine compartment roughly beside the air cleaner box. Your problem is
either the fan, the relay or the temp sender located in the radiator above
the transmission lines on the drivers side. (after 1991 they put the sender
in the thermostat elbow) My money is on your relay.
KH

"Snow" <snowball_2004@msn.com> wrote in message
news:HrS6d.18394$MD5.996517@news20.bellglobal.com. ..
> I'll assume you have a 4.0 under the hood. Most likely your problem is
> with
> the temp. switch that turns the electric fan on. Here's a couple easy
> tests to do.
> 1) connect the fan directly to the battery, if the fan spins its good.
> (by
> the sounds of it the fan is functioning)
> 2) I believe you said you have a/c. with the engine running select the
> heater control to defrost, as soon as you do the electric fan should start
> running. Next turn the heater off then turn it back on at one of the a/c
> settings again the fan should run.
>
> If the fan operates normally when you perform the above, I would say it is
> the temp. switch. I'm not sure if my 93 is the same layout as yours but
> the
> temp. switch on mine is located on the t-stat housing.
>
> Snow...
> "Richard" <rwrede2@hotmail.com> wrote in message
> news:10ln5inj6sg3v44@corp.supernews.com...
>> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
>> about cooling fans (electric) and it got me to wondering. My fan works
>> but
>> some times I notice it doesn't work. for instance, If I am sitting at a
>> drive up window or a long stop light etc... sometimes it over heats. that
>> is, until I put the transmission in park, then the fan kicks on. I have
> been
>> keeping a watch on it and sometimes it works normally and sometimes I
>> have
>> to put it in park, then it comes on normally after that.
>>
>> this sounds bizarre to me. am I nuts? is this possible?
>>
>> I have AC, it works fine then, I have a brand new radiator and fresh
>> coolant.
>>
>>
>
>

 

Your fan should come on automatically at around 210. Also it should always
be on whenever you turn on the air conditioning compressor (defrost AC etc).
There is a relay (square bosch style) on the drivers side fender wall in the
engine compartment roughly beside the air cleaner box. Your problem is
either the fan, the relay or the temp sender located in the radiator above
the transmission lines on the drivers side. (after 1991 they put the sender
in the thermostat elbow) My money is on your relay.
KH

"Snow" <snowball_2004@msn.com> wrote in message
news:HrS6d.18394$MD5.996517@news20.bellglobal.com. ..
> I'll assume you have a 4.0 under the hood. Most likely your problem is
> with
> the temp. switch that turns the electric fan on. Here's a couple easy
> tests to do.
> 1) connect the fan directly to the battery, if the fan spins its good.
> (by
> the sounds of it the fan is functioning)
> 2) I believe you said you have a/c. with the engine running select the
> heater control to defrost, as soon as you do the electric fan should start
> running. Next turn the heater off then turn it back on at one of the a/c
> settings again the fan should run.
>
> If the fan operates normally when you perform the above, I would say it is
> the temp. switch. I'm not sure if my 93 is the same layout as yours but
> the
> temp. switch on mine is located on the t-stat housing.
>
> Snow...
> "Richard" <rwrede2@hotmail.com> wrote in message
> news:10ln5inj6sg3v44@corp.supernews.com...
>> (89 Cherokee Pioneer 4.0L) I was reading some other posts in this group
>> about cooling fans (electric) and it got me to wondering. My fan works
>> but
>> some times I notice it doesn't work. for instance, If I am sitting at a
>> drive up window or a long stop light etc... sometimes it over heats. that
>> is, until I put the transmission in park, then the fan kicks on. I have
> been
>> keeping a watch on it and sometimes it works normally and sometimes I
>> have
>> to put it in park, then it comes on normally after that.
>>
>> this sounds bizarre to me. am I nuts? is this possible?
>>
>> I have AC, it works fine then, I have a brand new radiator and fresh
>> coolant.
>>
>>
>
>