Questions on Hydraulic Cooling Fan on 94 XLE

[Randy Wildebrandt]

I have a '94 XLE that we have owned for 12 years.

This summer it developed a whining noise that seems to be coming from the area of the fan behind the radiator.

This car has a hydraulic cooling fan. As I've looked into the problem I've come up with some question about this fan.

Here goes:

1. Is the fan supposed to run when the car is first started and is still cold? (Mine does).
   
2. Is the fan variable speed or does it have a few preset speeds? (I'd say mine is variable).
   
3. Should the fan be able to run at 'high' speed even when the car is idling? (Seems to me it should since there should be plenty of hydraulic fluid pressure).
   
4. What sensor inputs are used to control the operation of the fan?
   
5. Is the sensor for the temperature gauge at the same place as a control point for the fan? (My car never overheats. The temp gauge never goes past 1/2 way).
   
6. Was there some particular reason why this technology was used? (My understanding is that the hydraulic fan was only used for 2 years).
   

Thanks for any help!

[Leighcm]

I have a '94 XLE that we have owned for 12 years.

This summer it developed a whining noise that seems to be coming from the area of the fan behind the radiator.

This car has a hydraulic cooling fan. As I've looked into the problem I've come up with some question about this fan.

Here goes:

1. Is the fan supposed to run when the car is first started and is still cold? (Mine does).
   
2. Is the fan variable speed or does it have a few preset speeds? (I'd say mine is variable).
   
3. Should the fan be able to run at 'high' speed even when the car is idling? (Seems to me it should since there should be plenty of hydraulic fluid pressure).
   
4. What sensor inputs are used to control the operation of the fan?
   
5. Is the sensor for the temperature gauge at the same place as a control point for the fan? (My car never overheats. The temp gauge never goes past 1/2 way).
   
6. Was there some particular reason why this technology was used? (My understanding is that the hydraulic fan was only used for 2 years).
   

Thanks for any help!

In response to some of your questions:

1.) Yes, I think so.

2.) Variable.

(Okay, so it was just a couple of your questions. I've actually never had a problem with a fan, ever...)