HVAC fan switch

jcsmith

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2005
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3.7 V6
My fan switch stopped working. It was intermittent at first. A few times with the AC on I turned the fan off and theAC light stayed on. Does anyone have any suggestions to diagnose this issue. I appreciate any info.
 

Oliver Closehauf

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Cincinnati
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2005 Laramie
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Cummins 5.9
First thing would be to do a continuity check of the switches. Remove the radio bezel to get to the screws that hold the switch block in place, use a multimeter set to Ohms to check if the switches are closing or staying open. Check your connectors for corrosion when you have them apart.
 

HemiLonestar

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5.7 hemi
Is it the switch or the resistor?
 
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J

jcsmith

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Northampton Co. PA
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2005
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The switch was working on all speeds so I assume the resistor was good, but electrics are not my forte
 
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jcsmith

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2005
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Update; turned out to be the ignition switch on the left of steering column. Not the key tumbler. The contacts get hot and burned raising the resistance , and losing contact.This might help someone in the future. I was able to remove the shroud around the column and wiggle the switch , which got the fan working again while I waited for the new switch to come in.
 
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