RW> TW> IF your FAN was not responding the the engine block temperature   
   RW> TW> switch you had ANOTHER problem totally indepebndent to what the AC   
   RW> TW> system was reporting.   
      
   RW>I'll use the 1998 Service Manual to diagnose and repair what their testing   
   RW>reveals...it specifically applies to the 1998 product rather than some   
   RW>generic unknown source.   
      
   From the service manual of a 1998 5.7L F-car (Camaro/Firebird) here is   
   the descriptio of the cooling fan controls   
      
   Engine Cooling Fan Description - Electric   
   The electric cooling fans are used to cool engine coolant flowing   
   through the radiator. The fans are also used to cool the refrigerant   
   flowing through the A/C condenser.   
      
   The electric cooling fans are controlled by the PCM. The PCM controls   
   the ground path for the three cooling fan relays. The relays are used to   
   control the high current flow to power the cooling fan motors. Both fans   
   operate together. When minimum cooling is required, the PCM energizes   
   cooling fan relay #1 and both fans operate at low speed, since the fans   
   are connected in series through cooling fan relay #3. Cooling fan relay   
   #2 is open (not energized) and is not used for low speed operation of   
   the fans. When maximum cooling is required, the PCM energizes all three   
   cooling fan relays. The left fan is still powered through cooling fan   
   relay #1, but is now grounded through cooling fan relay #3. The right   
   fan is now powered directly through cooling fan relay #2 and both fans   
   operated at high speed.   
      
   The PCM will also enable the cooling fans after the ignition is turned   
   off. When the engine coolant temperature exceeds 113øC (235øF) and the   
   ignition is turned off, the cooling fans will be enabled on low speed   
   for 150 seconds.   
      
   Cooling Fans   
   The cooling fans are controlled by the PCM based on the   
   following inputs:   
      
   The A/C system.   
   The Engine Coolant Temperature (ECT) sensor.   
   The Vehicle Speed Sensor (VSS).   
      
   Looks like SEPERATE Functions to me controled by a combination of   
   Sensors and Relays.   
   ---   
    þ SLMR 2.1a þ Typo Tom strikes agaoin   
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