The fan keeps running when the engine is off and drains the battery. What would cause this?

2005 CHRYSLER PT CRUISER
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MCCLAIN
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I have a 2005 PT Cruiser and my husband & I went to dinner & when we came out our car wouldn't start. He noticed that the fan was still running, which caused our battery to die. What would make the fan keep running when the engine is off?
Jan 21, 2012 at 6:02 AM
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RASMATAZ
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A sticking fan relay or computer itself
Jan 21, 2012 at 6:04 AM
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PROAUTOTECH
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I believe that the fan gets constant power, but gets the ground from the fan switch. The fan can't turn on without a ground. So, either your fan switch is bad and stuck in ground mode, or the wire running to the fan has worn a hole or something and is grounded out on the frame or motor. The fan switch is very cheap and easy to replace. Let me know if you see any shorts on the wires and I will advise about the fan switch.
Jan 21, 2012 at 6:09 AM
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