It may be that the radiator core is partially blocked and needs to be flushed
Have you scanned the OBDII port to see if there are any 'codes' giving an indication of a problem?
There is a coolant temp sensor that sends the temp reading (actually a resistance value that changes with temp) to the ECU and at a programmed 'temp' setting the ECU operates the fan relay(s) which turn on the fans The number of relays it operates depends on the fan speed required and whether or not the A/C is operating.
Suggest that you may wish to check if the sensor is OK. I think that the temp sensor is located where the upper hose goes into the engine but not entirely sure of this
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There are 4 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link] (Scroll down to engine block fuse panel)
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There are 4 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link] (Scroll down to engine block fuse panel. Relays 8, 12, 14, 15)
If the temp sensor is OK check if the relay is operating. If not try another relay or check the relay's operate path.
It may be that the radiator core is partially blocked and needs to be flushed
Have you scanned the OBDII port to see if there are any 'codes' giving an indication of a problem?
There is a coolant temp sensor that sends the temp reading (actually a resistance value that changes with temp) to the ECU and at a programmed 'temp' setting the ECU operates the fan relay(s) which turn on the fans The number of relays it operates depends on the fan speed required and whether or not the A/C is operating.
Suggest that you may wish to check if the sensor is OK. I think that the temp sensor is located where the upper hose goes into the engine but not entirely sure of this
-
There are 3 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link]
+
There are 4 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link] (Scroll down to engine block fuse panel)
If the temp sensor is OK check if the relay is operating. If not try another relay or check the relay's operate path.
It may be that the radiator core is partially blocked and needs to be flushed
Have you scanned the OBDII port to see if there are any 'codes' giving an indication of a problem?
-
There is a coolant temp sensor that sends the temp reading (actually a resistance value that changes with temp) to the ECU and at a programmed 'temp' setting the ECU operates the fan relays which turns on the fans The number of relays it operates depends on the fan speed required and whether or not the A/C is operating.
+
There is a coolant temp sensor that sends the temp reading (actually a resistance value that changes with temp) to the ECU and at a programmed 'temp' setting the ECU operates the fan relay(s) which turn on the fans The number of relays it operates depends on the fan speed required and whether or not the A/C is operating.
Suggest that you may wish to check if the sensor is OK. I think that the temp sensor is located where the upper hose goes into the engine but not entirely sure of this
There are 3 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link]
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If the temp sensor is OK check if the relay is operating. If not try another relay or check the relay's operate path. Perhaps the wiring is corroded from the ECU etc.
+
If the temp sensor is OK check if the relay is operating. If not try another relay or check the relay's operate path.
Hi @pontiacuser2000 ,
It may be that the radiator core is partially blocked and needs to be flushed
Have you scanned the OBDII port to see if there are any 'codes' giving an indication of a problem?
There is a coolant temp sensor that sends the temp reading (actually a resistance value that changes with temp) to the ECU and at a programmed 'temp' setting the ECU operates the fan relays which turns on the fans The number of relays it operates depends on the fan speed required and whether or not the A/C is operating.
Suggest that you may wish to check if the sensor is OK. I think that the temp sensor is located where the upper hose goes into the engine but not entirely sure of this
There are 3 relays in the engine fuse block for the fans according to this [http://www.autogenius.info/pontiac-grand-am-2000-fuse-box-diagram/|link]
If the temp sensor is OK check if the relay is operating. If not try another relay or check the relay's operate path. Perhaps the wiring is corroded from the ECU etc.