Testing the Heater Blower switch..

Ambush

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Hey guys, my heater blower control switch ( the switch that lets you select High/Med/Low on the blower speed), was working properly. Now it's not working most of the time ...that is to say that when I go through the speeds the fan is not turning/blowing. Though sometimes it will blow, mainly it's not working.
I took apart the dash to get to the switch and do some tests. I unplugged the the switch from the socket/harness that's back in the dash - it's a 3 prong female connection. Anyway I put a test light to the that socket to see if it gets power ... I got nothing. But what I don't know is if that a normal reading for that socket or not? I tried the test with the key ON and still nothing on the test light. Can anyone tell me if that right or not. Again the blower switch and fan have worked before.
Also there's the switch itself. What a good way to test to see of that is the culprit?

Oh and I'm going to need a AC Heater vacuum switch Part # 2096084 or 2587564, if anyone has one.

I'm attaching pics of the socket I tested and the switch that connect to it .... Any thoughts or help are most welcome. 1965 Imperial Crown

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Good Morning
Downloading the Service Manual Service Manuals – MyMopar It is under 1965 Chrysler but it also include Imperial. This will be your beat best in troubleshooting.
The actual troubleshooting will depend on your electrical skills.
Omni
 
Is there another switch that is disconnected? The one that selects heat/def/ac. I think that needs to be connected and not in the off position in order to have power to the fan switch. I believe that will provide the power for the low speed and then the switch will let you select med or high fan speed.
 
Is there another switch that is disconnected? The one that selects heat/def/ac. I think that needs to be connected and not in the off position in order to have power to the fan switch. I believe that will provide the power for the low speed and then the switch will let you select med or high fan speed.
This is how it works in a 68. I guessing it's the same.
 
Is there another switch that is disconnected? The one that selects heat/def/ac. I think that needs to be connected and not in the off position in order to have power to the fan switch. I believe that will provide the power for the low speed and then the switch will let you select med or high fan speed.
Yup I think you're right. I have the service manual but I could not find what I was specifically looking for. I think that wire does not supply any constant power, but rather the power comes in on another connection to the heater vacuum switch assembly and then is fed out and through to the fan speed switch once it's turned "on" and engaged. I'll test that once I get a new Vacuum switch and see.
Still my worry is that the ultimate problem is the blower motor ...from what I read in the Manual, it sounds difficult to remove and replace or even to test... I wonder if there is a better explanation of the process of installing a new blower motor from someone w/ easier understood jargon, compared to what's in the manual.
 
The fan switch itself is easy enough to test with a multimeter, just check for continuity on the correct wires depending on switch position. I'm not sure about testing or removing the fan but you may be able to run a jumper to the resistor block or the fan itself to see if it works.
 
The black wire is power in (probably from the plastic push button switch).
Black to brown is low
Black to green is high

I have a 2587564, NOS MoPar, if you are still looking.
 
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