AC blower issues
#1
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AC blower issues
This is on my 89.
The blower motor went out. I had the 12v to the motor and nothing. I went to Napa and got another one. This one ran for about 10 min and then blew the fused link for high speed. It then ran on low speed for awhile and then blew the fuse for the AC controls.
I replaced the fused link with an in line fuse. I took the motor back to Napa and got another one. The surprise is that it blows the in line fuse immediately and will blow the AC control fuse if left on low for a few seconds. This whole time neither motor ran except for the initial time the fused link blew.
I did a little test using my alligator clips and an inline fuse to connect directly to the battery. Now the motor runs fine at full speed like it should.
Here is the kicker, if I hold the fan while it is running (connected to the battery) and touch the motor housing to a ground it blows the fuse. I don't see how it would be installed in the car without the housing being grounded. It uses metal screws to attach it to the heater box which is metal. And why would you want it like that anyways?
Am I wrong by thinking there is a manufacturing problem with these motors, or is there something else wrong with my wiring.
I have the FSM and have traced all the wiring through the AC circuits and blower circuits and nothing is out of line. (Just want to let you know that I do have an extensive electronics background)It only happens when the blower is turned on. The compressor and everything else works fine and then as soon as I turn on the blower it will blow the fuse.
Should I get a new motor somewhere else or shoul I go to Napa and complain first?
The blower motor went out. I had the 12v to the motor and nothing. I went to Napa and got another one. This one ran for about 10 min and then blew the fused link for high speed. It then ran on low speed for awhile and then blew the fuse for the AC controls.
I replaced the fused link with an in line fuse. I took the motor back to Napa and got another one. The surprise is that it blows the in line fuse immediately and will blow the AC control fuse if left on low for a few seconds. This whole time neither motor ran except for the initial time the fused link blew.
I did a little test using my alligator clips and an inline fuse to connect directly to the battery. Now the motor runs fine at full speed like it should.
Here is the kicker, if I hold the fan while it is running (connected to the battery) and touch the motor housing to a ground it blows the fuse. I don't see how it would be installed in the car without the housing being grounded. It uses metal screws to attach it to the heater box which is metal. And why would you want it like that anyways?
Am I wrong by thinking there is a manufacturing problem with these motors, or is there something else wrong with my wiring.
I have the FSM and have traced all the wiring through the AC circuits and blower circuits and nothing is out of line. (Just want to let you know that I do have an extensive electronics background)It only happens when the blower is turned on. The compressor and everything else works fine and then as soon as I turn on the blower it will blow the fuse.
Should I get a new motor somewhere else or shoul I go to Napa and complain first?
#2
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My Chilton'* manual shows two wires going to the blower motor. Orange (12v) & Black (ground). Check the resistance of the blower motor by connecting the meter to the black & orange wires/terminals on the blower. Now check the resistance between the orange wire/terminal & the blower motor housing. Let us know what you find.
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Actually my leads are purple and black (and this is what my FSM shows also). I have done a resistance check through the motor. It fluctuates like it should on a DC motor with brushes, but when I touch the housing to ground and rotate the shaft I get a constant 5 ohms. This is why I believe there is something in the motor shorted to the housing.
If I check each lead to the housing I also get the constant 5 ohms on each.
If I check each lead to the housing I also get the constant 5 ohms on each.
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I ended up getting a new motor from Shuck'* and it read an open from the leads to the housing. Installed it and it works great.
Went to Napa and they check out both motors and they read the same. They refunded my money and said they would file a report to get the parts checked out.
So, as a heads up, if you need a blower motor, check yours out if you get it from Napa.
Went to Napa and they check out both motors and they read the same. They refunded my money and said they would file a report to get the parts checked out.
So, as a heads up, if you need a blower motor, check yours out if you get it from Napa.
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