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Radiator Fan question

  #1  
Old 07-08-2011 | 11:57 AM
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Default Radiator Fan question

I recently got a 97 Civic and noticed that the radiator fan isn't coming on. I checked the voltage on the fan plug located next to the radiator overflow reservoir. I got nothing. Is there supposed to be constant power to that plug? If so where should I go from here?
 
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Old 07-08-2011 | 12:20 PM
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The fan switch is located on the thermostat housing. Unplug the 2P connector and short the plug with a jumper wire. The fan should now run continuously when the key is in ON(II). Does it?
 
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Old 07-08-2011 | 02:42 PM
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Originally Posted by RonJ
The fan switch is located on the thermostat housing. Unplug the 2P connector and short the plug with a jumper wire. The fan should now run continuously when the key is in ON(II). Does it?
Yes Sir, The fan does run when the plug is shorted out. I guess I need a new switch?
 

Last edited by bmboll; 07-08-2011 at 02:51 PM.
  #4  
Old 07-08-2011 | 02:50 PM
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Is the engine overheating? Normally, the fan doesn't need to run much.

If it was overheating while sitting still, test drive with the jumper in and the fan running all the time. If there is then no overheating, replace the thermal switch.
 
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Old 07-08-2011 | 03:29 PM
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MK is right. Civic engines run cool, so you may need to drive the car for 10 minutes and then let it idle for 5-10 minutes to see the fan run. If it never runs, then start by bleeding the cooling system. If the problem persists, replace the switch.
 
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Old 07-08-2011 | 03:32 PM
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To make a short story long....I changed the radiator fluid a couple months back. When doing that I noticed that the radiator cap was broken. The plunger had broken off so I replaced it. Right after that I started getting leaks in the radiator. It is leaking in the area top of the radiator is "crimped" on. yada yada yada...I'm wondering if the radiator is getting to hot and building up to much pressure.

The short answer is some times when at a stop light the temp gauge goes up a little.
 
  #7  
Old 07-08-2011 | 03:35 PM
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If the radiator is leaking, replace it immediately and then bleed the cooling system. Make sure to use only 50:50 coolant rather than water in the cooling system.
 
  #8  
Old 07-08-2011 | 03:48 PM
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I'll also add that it is F'n hot here is Tucson, AZ
 
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Old 07-08-2011 | 04:04 PM
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At least it's arid.
 
  #10  
Old 07-08-2011 | 04:11 PM
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+1 Leaking radiator needs to be replaced.

The reason it didn't leak (much) before with the other broken cap is because the other cap didn't let normal pressure build up. Pressure is designed to build up to resist boiling of the coolant (consider Three Mile Island...).
 

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