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AC/heater blower problems

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Old Mar 13, 2020 | 12:55 PM
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AC/heater blower problems

Have an 85 f250 my original heater blower went out so I changed it new one died in 30 days so I changed it and the fuse yesterday it still won't turn on any ideas the first blower was weaker than the original it didn't blow as well as the original thank you for your help
 
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Old Mar 13, 2020 | 01:04 PM
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blower resistor, blower switch, fried connectors in the wiring to it.

EDIT: Fuse #9 I believe is your main fuse for the blower
 
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Old Mar 13, 2020 | 01:12 PM
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Originally Posted by lonewolf_
blower resistor, blower switch, fried connectors in the wiring to it.
Oh boy where should I start and what tools will I need?
 
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Old Mar 13, 2020 | 01:23 PM
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Originally Posted by Dieseloholic1
Oh boy where should I start and what tools will I need?
here is a good place......




NOTE: this shows Both versions with and without AC but the components are Marked to indicate which is which
IF you need help with the schematic tell me which system you have and I can Highlight or edit this image to better suit your needs.
 
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Old Mar 13, 2020 | 01:28 PM
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the blower Resistor is the first Place I would start looking. ..... that is assuming you have tested the blower motor by applying 12 volts to it direct.
 
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Old Mar 13, 2020 | 01:42 PM
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Originally Posted by lonewolf_
here is a good place......




NOTE: this shows Both versions with and without AC but the components are Marked to indicate which is which
IF you need help with the schematic tell me which system you have and I can Highlight or edit this image to better suit your needs.
I have ac with mine
 
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Old Mar 13, 2020 | 01:42 PM
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Originally Posted by lonewolf_
the blower Resistor is the first Place I would start looking. ..... that is assuming you have tested the blower motor by applying 12 volts to it direct.
Sweet I'll start with that where is it located
 
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Old Mar 13, 2020 | 01:47 PM
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ok with either type system IF you put your Blower switch to the High Position the Blower should run and the Blower resistor is not used with that speed...

so IF it will not work on High then it is not the Blower Resistor
 
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Old Mar 13, 2020 | 02:03 PM
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Originally Posted by lonewolf_
ok with either type system IF you put your Blower switch to the High Position the Blower should run and the Blower resistor is not used with that speed...

so IF it will not work on High then it is not the Blower Resistor
Good to know I'll try that when I get home if that doesn't work what would you try next? I'm asking now because getting a cell signal where I live is hard so bi don't have internet often thank you for your help
 
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Old Mar 13, 2020 | 02:59 PM
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I'm going to buy a switch how hard is it to change?
 
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Old Mar 13, 2020 | 04:40 PM
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ok here is a simplified diagram ... it says Fuse 14 but I think it is really Fuse 9 .. the Resistor assy is under the hood near the blower motor mounted in the Plenum ...
as you can see by the diagram it can be either the function switch or the blower switch causing an issue .. but I would follow the schematic and check power in the various points to isolate the problem.



Print off a couple copies then you can reference it ... if you using a Laptop then just save image and you will have it.. I don't use smartphones so I don't know their capabilities
 
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Old Mar 13, 2020 | 05:01 PM
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Originally Posted by lonewolf_
ok here is a simplified diagram ... it says Fuse 14 but I think it is really Fuse 9 .. the Resistor assy is under the hood near the blower motor mounted in the Plenum ...
as you can see by the diagram it can be either the function switch or the blower switch causing an issue .. but I would follow the schematic and check power in the various points to isolate the problem.



Print off a couple copies then you can reference it ... if you using a Laptop then just save image and you will have it.. I don't use smartphones so I don't know their capabilities
Thank you so much I saved it I'll work on it asap we dipped down into the 30s and lower again I'll wait a few days since I'm not going anywhere again before it warms up
 
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Old Mar 17, 2020 | 04:12 PM
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Got my blower running still seems to be weaker than my original Ford one for some reason any ideas
 
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Old Mar 17, 2020 | 05:02 PM
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well, not all motors are created equal....

but you can check a few things...... is motor running in the right direction? does it blow strong in the Defrost Mode, if so it is probably running in the correct direction.
last check that all the doors are working especially the Blend door.

when the blower switch is in the HI position there is no speed reduction done by the Blower resistor.... so you can jumper the Motor direct to the Battery to verify it is running the same as it does in the HI switch position (what this does is eliminates a point of high resistance in the blower wiring)
 
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Old Mar 17, 2020 | 06:28 PM
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Originally Posted by lonewolf_
well, not all motors are created equal....

but you can check a few things...... is motor running in the right direction? does it blow strong in the Defrost Mode, if so it is probably running in the correct direction.
last check that all the doors are working especially the Blend door.

when the blower switch is in the HI position there is no speed reduction done by the Blower resistor.... so you can jumper the Motor direct to the Battery to verify it is running the same as it does in the HI switch position (what this does is eliminates a point of high resistance in the blower wiring)
you have a great point

I'll have to check the defrost mode actually now that I think about it even when I pick defrost or even floor it still comes out the vents I'll definitely check that stuff out thank you again for always helping me
 
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