Blower motor, again!!!!!!
Le Mans Master
Joined: Jun 2006
Posts: 6,393
Likes: 1,225
From: Tampa Florida
OK, the local auto parts store didn't have the Borg Warner relay, or an equivalent. Said they could get one in 2-3 days. So I went back to the garage to play. With the switch set to "max", if I jumped the purple wire to ground, the blower motor came on max. Does this mean the relay is bad?
The purple wire needs battery voltage and is waiting to be connected to the orange wire via the hi speed relay. The orange wire gets constant battery voltage supplied by the horn relay battery connection.
I'm an old '70's telephone industry guy, so relays and power plants were my life.
Last edited by 71 Green 454; Sep 8, 2015 at 11:36 AM.
Former Vendor
Joined: Aug 2006
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I removed the relay, checked that the relay operated when I put battery and ground on the winding contacts. With the relay operated, I verified that I had continuity between the fixed and make contacts, this is where the purple and orange wires connect.
No! It means you have battery on the other side of the blower motor, but you should have a ground. Go back and read the first sentence in post #2.
The purple wire needs battery voltage and is waiting to be connected to the orange wire via the hi speed relay. The orange wire gets constant battery voltage supplied by the horn relay battery connection.
I'm an old '70's telephone industry guy, so relays and power plants were my life.
No! It means you have battery on the other side of the blower motor, but you should have a ground. Go back and read the first sentence in post #2.
The purple wire needs battery voltage and is waiting to be connected to the orange wire via the hi speed relay. The orange wire gets constant battery voltage supplied by the horn relay battery connection.
I'm an old '70's telephone industry guy, so relays and power plants were my life.
The purple wire to the blower motor is the power wire. Willcox
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
I removed the relay, checked that the relay operated when I put battery and ground on the winding contacts. With the relay operated, I verified that I had continuity between the fixed and make contacts, this is where the purple and orange wires connect.
No! It means you have battery on the other side of the blower motor, but you should have a ground. Go back and read the first sentence in post #2.
The purple wire needs battery voltage and is waiting to be connected to the orange wire via the hi speed relay. The orange wire gets constant battery voltage supplied by the horn relay battery connection.
I'm an old '70's telephone industry guy, so relays and power plants were my life.
No! It means you have battery on the other side of the blower motor, but you should have a ground. Go back and read the first sentence in post #2.
The purple wire needs battery voltage and is waiting to be connected to the orange wire via the hi speed relay. The orange wire gets constant battery voltage supplied by the horn relay battery connection.
I'm an old '70's telephone industry guy, so relays and power plants were my life.
With the fan switch in the "off" position, the blue and purple wires should show no voltage to ground, and the orange wire should show 12+ volts to ground, right?
In the first 3 speeds, the purple at the relay should show 12+ volts because it is getting its power from the connector on the evaporator box, the orange wire should still show 12 volts, and the blue wire should still show no volts, correct?
If that is correct, then in the "max" speed, the blue, orange, and purple wires should all show 12 volts. If they do, and the motor doesn't come on, the relay has to be bad. Does that make sense?
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Here is what I just tested in the garage. All are voltages at the relay:
Position................Blue............ ..Orange..............Purple
Off.........................12.......... .......12....................0
Low........................12........... ......12...................6
Med.......................12............ ......12...................7
High......................12............ ......12...................8
Max.......................12............ ......12...................0
What struck me is that the blue wire was always hot. So I unplugged the connector, and ran the same test again, this was the result:
Position................Blue............ ..Orange..............Purple
Off..........................0.......... .......12....................0
Low.........................0........... ......12...................6
Med........................0............ ......12...................7
High.......................0............ ......12...................8
Max.......................12............ ......12...................0
This looks like what I expected from looking at the diagram above. The Purple wire on max WOULD be 12, if the relay were connected and working properly, but with the relay not connected, I would expect a 0. I don't know what is up with this relay, but it is certainly doing something funky to have the blue wire hot in all positions.
Position................Blue............ ..Orange..............Purple
Off.........................12.......... .......12....................0
Low........................12........... ......12...................6
Med.......................12............ ......12...................7
High......................12............ ......12...................8
Max.......................12............ ......12...................0
What struck me is that the blue wire was always hot. So I unplugged the connector, and ran the same test again, this was the result:
Position................Blue............ ..Orange..............Purple
Off..........................0.......... .......12....................0
Low.........................0........... ......12...................6
Med........................0............ ......12...................7
High.......................0............ ......12...................8
Max.......................12............ ......12...................0
This looks like what I expected from looking at the diagram above. The Purple wire on max WOULD be 12, if the relay were connected and working properly, but with the relay not connected, I would expect a 0. I don't know what is up with this relay, but it is certainly doing something funky to have the blue wire hot in all positions.
Le Mans Master
Joined: Jun 2006
Posts: 6,393
Likes: 1,225
From: Tampa Florida
I'm really struggling with this. I don't think I understand a lot of your terminology. I watched a couple videos on how relays work to try to educate myself more, but it didn't seem to help. Sorry to be such a dolt, but lets try coming at this another way.
With the fan switch in the "off" position, the blue and purple wires should show no voltage to ground, and the orange wire should show 12+ volts to ground, right? Correct
In the first 3 speeds, the purple at the relay should show 12+ volts because it is getting its power from the connector on the evaporator box, the orange wire should still show 12 volts, and the blue wire should still show no volts, correct? Purple wire-no, the purple wire will not have 12 volts until the relay operates. Orange wire-yes because it's being fed voltage from the horn relay terminal. The relay is for hi-speed blower operation only. Blue wire-no, not until you put the fan switch to high to operate the relay.
If that is correct, then in the "max" speed, the blue, orange, and purple wires should all show 12 volts. If they do, and the motor doesn't come on, the relay has to be bad. Does that make sense?
With the fan switch in the "off" position, the blue and purple wires should show no voltage to ground, and the orange wire should show 12+ volts to ground, right? Correct
In the first 3 speeds, the purple at the relay should show 12+ volts because it is getting its power from the connector on the evaporator box, the orange wire should still show 12 volts, and the blue wire should still show no volts, correct? Purple wire-no, the purple wire will not have 12 volts until the relay operates. Orange wire-yes because it's being fed voltage from the horn relay terminal. The relay is for hi-speed blower operation only. Blue wire-no, not until you put the fan switch to high to operate the relay.
If that is correct, then in the "max" speed, the blue, orange, and purple wires should all show 12 volts. If they do, and the motor doesn't come on, the relay has to be bad. Does that make sense?
Try this, with the connectors removed from the relay, do you have standing ground on the black wire? With the ignition on and the fan switch set to hi, do you have 12 volts on the blue wire?
This would be a good opportunity for you to see the inside of the relay. Remove the cover and locate the winding contacts first. That is where the smaller gauge blue wire and the smaller gauge black wire will connect to operate the relay when 12 volts is applied via the blue wire.
Next, locate the fixed contact terminal and the make contact terminal. These are the ones that close when the relay operates, thus connecting the orange wire to the purple wire. Also, look at the contacts to see if they are burnt.
Le Mans Master
Joined: Jun 2006
Posts: 6,393
Likes: 1,225
From: Tampa Florida
Here is what I just tested in the garage. All are voltages at the relay:
Position................Blue............ ..Orange..............Purple
Off.........................12.......... .......12....................0
Low........................12........... ......12...................6
Med.......................12............ ......12...................7
High......................12............ ......12...................8
Max.......................12............ ......12...................0
What struck me is that the blue wire was always hot. So I unplugged the connector, and ran the same test again, this was the result:
Position................Blue............ ..Orange..............Purple
Off..........................0.......... .......12....................0
Low.........................0........... ......12...................6
Med........................0............ ......12...................7
High.......................0............ ......12...................8
Max.......................12............ ......12...................0
This looks like what I expected from looking at the diagram above. The Purple wire on max WOULD be 12, if the relay were connected and working properly, but with the relay not connected, I would expect a 0. I don't know what is up with this relay, but it is certainly doing something funky to have the blue wire hot in all positions.
Position................Blue............ ..Orange..............Purple
Off.........................12.......... .......12....................0
Low........................12........... ......12...................6
Med.......................12............ ......12...................7
High......................12............ ......12...................8
Max.......................12............ ......12...................0
What struck me is that the blue wire was always hot. So I unplugged the connector, and ran the same test again, this was the result:
Position................Blue............ ..Orange..............Purple
Off..........................0.......... .......12....................0
Low.........................0........... ......12...................6
Med........................0............ ......12...................7
High.......................0............ ......12...................8
Max.......................12............ ......12...................0
This looks like what I expected from looking at the diagram above. The Purple wire on max WOULD be 12, if the relay were connected and working properly, but with the relay not connected, I would expect a 0. I don't know what is up with this relay, but it is certainly doing something funky to have the blue wire hot in all positions.
Your picture.....
Take the cover off of the relay. The blue and black wires operate the relay when connected to the windings. When relay operates, the orange and purple wires complete a path supplying 12 volts for hi speed fan operation.
Last edited by 71 Green 454; Sep 8, 2015 at 03:17 PM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,850
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
He has the wrong relay (up a bit and you'll see he has a five terminal relay, should be four) and until it's replaced he's going to have issues. I don't know what relay you have and you could pull the cover off and see the circuit and then possibly move the wires to allow the relay to function the way the correct relay functions... is it possible? Without seeing he inside of the relay I can't tell you. But what I would do is just get the correct relay and your problems will probably be solved.
IMHO,
Willcox
IMHO,
Willcox
Le Mans Master
Joined: Jun 2006
Posts: 6,393
Likes: 1,225
From: Tampa Florida
He has the wrong relay (up a bit and you'll see he has a five terminal relay, should be four) and until it's replaced he's going to have issues. I don't know what relay you have and you could pull the cover off and see the circuit and then possibly move the wires to allow the relay to function the way the correct relay functions... is it possible? Without seeing he inside of the relay I can't tell you. But what I would do is just get the correct relay and your problems will probably be solved.
IMHO,
Willcox
IMHO,
Willcox
OK, get the correct relay and lets see what happens.
Good luck!
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Former Vendor
Joined: Aug 2006
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I just took both types of relays apart... the five terminal is not going to work for you. That design is the same style used on the 1968-1972 wiper system and is a switching type relay, the type used on your car is a pass through style where it's passing power from (on the three terminal side) left to right with power being the lower terminal.
If that makes sense to you (hope it does) if it doesn't I took pictures too...
If that makes sense to you (hope it does) if it doesn't I took pictures too...
Thread Starter
Team Owner
Joined: Jul 2008
Posts: 23,419
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
I'm sorry if this is painful for you guys, but I am learning a ton here!
Yes, I have a 5 terminal relay instead of 4. Here is a pic of the relay:
I took it apart, here is a pic of that:
It is a little hard to tell from the picture, but the two ends of the wire on the electromagnet attach to the two spades on the "ground" end of the relay. Therefore, it is laid out incorrectly, since the blue and black wires need to be connected there, but instead there was a black wire and an empty spade. In the unactivated position, the orange wire connector is connected to the blue wire connector, which is why the blue wire was always hot, because the orange wire is always hot from the horn relay connection. If the switch had activated, the orange wire would have connected to the purple wire, but since there was never a current over the switch side, that never happened.
I went to a different auto parts store, and they will have a correct relay for me by 8 am tomorrow. I am optimistic this will correct the current problem!
Huge thanks to Willcox and 71 Green 454 for the help and education!
PK
Yes, I have a 5 terminal relay instead of 4. Here is a pic of the relay:
I took it apart, here is a pic of that:
It is a little hard to tell from the picture, but the two ends of the wire on the electromagnet attach to the two spades on the "ground" end of the relay. Therefore, it is laid out incorrectly, since the blue and black wires need to be connected there, but instead there was a black wire and an empty spade. In the unactivated position, the orange wire connector is connected to the blue wire connector, which is why the blue wire was always hot, because the orange wire is always hot from the horn relay connection. If the switch had activated, the orange wire would have connected to the purple wire, but since there was never a current over the switch side, that never happened.
I went to a different auto parts store, and they will have a correct relay for me by 8 am tomorrow. I am optimistic this will correct the current problem!
Huge thanks to Willcox and 71 Green 454 for the help and education!
PK
Le Mans Master
Joined: Jun 2006
Posts: 6,393
Likes: 1,225
From: Tampa Florida
Good luck!
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,850
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
That relay isn't going to cut it PK... get the correct one (which I see you have coming) .......... If you knew how the original relay worked in comparison to the one you have you'd understand.... they are so different.. I was looking for a way to make the one you had work but it's just not going to happen based on the function and difference of the two.
The relay you have is a switching type that switches continuity from the right (on the three side) to the right on the two side connector.... Not going to fly with what is needed...
You'll have to trust me on this one, trash that relay and get the right one.
Regards,
Ernie
The relay you have is a switching type that switches continuity from the right (on the three side) to the right on the two side connector.... Not going to fly with what is needed...
You'll have to trust me on this one, trash that relay and get the right one.
Regards,
Ernie
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Team Owner
Joined: Jul 2008
Posts: 23,419
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
You mentioned grounding the purple wire to ground and the blower motor operated. Just make sure that 12 volts to purple is correct and not ground before installing the relay. Always best to perform basic tests first.
Good luck!
Good luck!
Thread Starter
Team Owner
Joined: Jul 2008
Posts: 23,419
Likes: 22
From: In limbo
St. Jude Donor '13-'15, '17 thru '22
That relay isn't going to cut it PK... get the correct one (which I see you have coming) .......... If you knew how the original relay worked in comparison to the one you have you'd understand.... they are so different.. I was looking for a way to make the one you had work but it's just not going to happen based on the function and difference of the two.
The relay you have is a switching type that switches continuity from the right (on the three side) to the right on the two side connector.... Not going to fly with what is needed...
You'll have to trust me on this one, trash that relay and get the right one.
Regards,
Ernie
The relay you have is a switching type that switches continuity from the right (on the three side) to the right on the two side connector.... Not going to fly with what is needed...
You'll have to trust me on this one, trash that relay and get the right one.
Regards,
Ernie
I picked up the new relay this morning, and tonight installed and connected it. The blower motor switch now works as designed!
I can't tell you how much I appreciate all the help in this thread, mostly from Willcox and 71 Green 454! You guys have been so patient with me, when I know I am a "tough pupil" on electrical stuff! Thank you!
After installing and testing the relay, I finished re-assembling everything under the hood of my car, and closed the hood for the first time in more than a year. My headlights were back together before I started the switch diagnosis, so I just have to put the interior back together and I will be back out on the road! I am really looking forward to it!
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,850
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Yes, last night when I took the relay out of the car, brought it to the kitchen table, took it apart, and got up close and personal with it (the pictures are above), I learned a lot. I think I didn't really understand what relays did and how they worked until I did that. But you are right, that relay was never going to work, at least not without some serious Bubbaing of the wires. The new one was $20, and although I have been out of work for a long time, I'm still not that cheap!
I picked up the new relay this morning, and tonight installed and connected it. The blower motor switch now works as designed!
I can't tell you how much I appreciate all the help in this thread, mostly from Willcox and 71 Green 454! You guys have been so patient with me, when I know I am a "tough pupil" on electrical stuff! Thank you!
After installing and testing the relay, I finished re-assembling everything under the hood of my car, and closed the hood for the first time in more than a year. My headlights were back together before I started the switch diagnosis, so I just have to put the interior back together and I will be back out on the road! I am really looking forward to it!
I picked up the new relay this morning, and tonight installed and connected it. The blower motor switch now works as designed!
I can't tell you how much I appreciate all the help in this thread, mostly from Willcox and 71 Green 454! You guys have been so patient with me, when I know I am a "tough pupil" on electrical stuff! Thank you!
After installing and testing the relay, I finished re-assembling everything under the hood of my car, and closed the hood for the first time in more than a year. My headlights were back together before I started the switch diagnosis, so I just have to put the interior back together and I will be back out on the road! I am really looking forward to it!
Regards,
Ernie
Thread Starter
Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
I believe it does. I could turn it on, and reach under the dash and feel some cool air, it just wouldn't blow into the cabin. Same with heat, it would feel nice and warm up under there, but no flow into the cabin.
Thread Starter
Team Owner
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
The good news for me is that all of the problems I set out to fix on this project, except the one I bailed on, are fixed. I am in total re-assembly mode now, looking forward to the first drive in over a year!
Instructor
Joined: May 2016
Posts: 111
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From: Chapel Hill NC
can someone explain the exact wiring at the blower motor
I assume the purple is the hot/power
what are the 2 dotted line black wires (labelled 14 B and 18B), both grounds?
I see one says ground to starting motor (presume means starter)
what about the other? another ground? and where does it go and attach?
does anyone have a picture of the actual wires and where they connect to the blower motor? mine is confusing, I have a single wire and a wire plug (at least that I can see) attaching to my blower motor
thanks
I assume the purple is the hot/power
what are the 2 dotted line black wires (labelled 14 B and 18B), both grounds?
I see one says ground to starting motor (presume means starter)
what about the other? another ground? and where does it go and attach?
does anyone have a picture of the actual wires and where they connect to the blower motor? mine is confusing, I have a single wire and a wire plug (at least that I can see) attaching to my blower motor
thanks
Thread Starter
Team Owner
Joined: Jul 2008
Posts: 23,419
Likes: 22
From: In limbo
St. Jude Donor '13-'15, '17 thru '22
can someone explain the exact wiring at the blower motor
I assume the purple is the hot/power
what are the 2 dotted line black wires (labelled 14 B and 18B), both grounds?
I see one says ground to starting motor (presume means starter)
what about the other? another ground? and where does it go and attach?
does anyone have a picture of the actual wires and where they connect to the blower motor? mine is confusing, I have a single wire and a wire plug (at least that I can see) attaching to my blower motor
thanks
I assume the purple is the hot/power
what are the 2 dotted line black wires (labelled 14 B and 18B), both grounds?
I see one says ground to starting motor (presume means starter)
what about the other? another ground? and where does it go and attach?
does anyone have a picture of the actual wires and where they connect to the blower motor? mine is confusing, I have a single wire and a wire plug (at least that I can see) attaching to my blower motor
thanks
[/QUOTE]It is not exactly correct for my car, because there is no purple wire in my blower motor connector on top of the evaporator box. I'm still not sure why, but my blower is working, but burns a fuse once in a while.