electric radiator fan not turning on

2000 JEEP GRAND CHEROKEE LAREDO
180,000 MILES • 4.0L • 6 CYL • 4WD • AUTOMATIC
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JONNYB_2010
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I have replace the relay once already and the coolant temperature sensor. The fan motor itself is turning on with direct power and its resistance is 2.6 ohms so its only drawing about 5 amps. I just recently replaced the pcm due to another issue but the fan didn't work before that anyways. Any ideas?
Dec 3, 2015 at 4:14 AM
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HMAC300
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check the ground and check if there is a good connection at relay. the pcm controls this so also check connection at ect. see if the relay is sending power to fan it may be a broken or chafed wire as well.
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Dec 3, 2015 at 6:25 AM
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JONNYB_2010
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Ground read .5 ohms. The grey power wire 12 Volts. The green wire to the pcm read 5-6 volts when car was running and a/c turned on... Is it possible for that control wire to be shorting out and that would be why I am not see the 12v it should have
Dec 3, 2015 at 6:54 AM
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HMAC300
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I fyou looked at the drawing I sent it shows the green wire going to fan not pcm. it shold have 12 volts. it may be a chafed wire or a bad connection at relay, make sure they are good then put dielectric grease on it for a better connection.
Dec 3, 2015 at 6:58 AM
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JONNYB_2010
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there are two green wires on the relay. the first one is the control wire and the second goes to the fan motor
Dec 3, 2015 at 7:22 AM
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JONNYB_2010
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I just thought I should be seeing 12v from the control wire. I probably have a shorted wire somewhere I will just have to pull the battery tray and trace the wires.
Dec 3, 2015 at 7:37 AM
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HMAC300
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the control wire is dk blue/pink and that should have 5 volts
Dec 3, 2015 at 7:53 AM
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JONNYB_2010
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Ok... That's good news... I will trace the wires and see if that is my issue... the relay could have failed again but that is usually from something being wrong with the fan.
Dec 3, 2015 at 7:58 AM