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Power Window Relay Setup

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Not young and cocky, I do look at things differently than a lot of people. I was a kid when I started fixing valve stuff because that's all there was. B+ voltages, just rang a bell. My dad had a vibrator based radio in a 1962 vehicle. I had a Blaupunkt AM/FM/SW radio which the dial was layed out in wavelength in a 1973 vehicle. I was introduced to Sams Photofact as a pre-teen. So, I'm like 10 YO and playing with circuits that generate 600 V or more. I did see the Apollo moon landing live broadcast.
 
Here is a partial answer to your question. When I use the 5 pin switch wired as shown in my diagram in posting one, the relays click when I try to move the driver window up or down. The windows, however, do not move. Please note though that there was a day not too long ago when the driver window was going up and down with the 5 pin switch. Now, I said in one of my postings that the switch is rated for 30 amps. I know for sure that the 6 pin DPDT switches are rated for 30 amps, but I am not sure about the 5 pin switches. So, I have to apologize to Mike. He may have been right when he said that the switchs are not rated for the current. I purchased the 5 pin on Ebay and they came from China. They were represented as 30 amp but sometimes when you get stuff from China the stuff is not as represented or is defective.

With respect to the 6 pin DPDT switches and whether the relays click, I will tell you for sure tomorrow, but as I recall they do not when the DPDT switches are wired as shown in the diagram in posting 1. So, you may be correct that the wiring is wrong in that diagram for this application. If so, I ask what is the correct way. I am sorry Kiss. Even with your explanation, I still do not understand how you propose these switches be wired. (I saw the Apollo landing live also. :) )

Much thanks again to all. bwilliams you do what you want but I wish you would hang. I am slow, not like mentally slow, but slow at getting things done you could say with respect to electronics, and I guess that's in a large part because my knowledge is not that extensive. I take it slow so as to limit my mistakes. So if will run over a little on this one, please don't hold it against me.

Talk to everyone soon.
 
Then let's let someone else do the talking: https://www.robotroom.com/DPDT-Bidirectional-Motor-Switch.html

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Switched have both an AC and DC ratings. They also have a current and voltage ratings. Some switched may not even be able to be used on AC or even DC. You have to respect both ratings. Some switches even have the the amount of switching current is different that the static current. Some have to switched with no potential across them. You have switches rated for horsepower use.

One common example is the reversing switch on a ceiling fan. You don't move it while the fan is on.

==

One thing I used to do when training is ask:
1) Want a recipie?
2) Do you want to understand?
3) Do you prefer pictures?

It does turn out that memory is visual, verbal and Kinesthetic. Te last one can be described as how you migh learn to ride a bike or repetition. This question has already been asked, but not explained why. You eventually understood me (or someone else/website) so, it looks like abstraction is not your thing. It also might mean that schematics are not your thing.
Don't know.

Yea, me to in terms of learning. I had to figure out just what I need to to do in school after flunking out to manage a degree with a 4.0 GPA at another school. I did come back to the flunked out school and got an engineering degree.
For me I memorize Kinetically and I did not connect that I had to do the problems with the book closed. School became, "How do I get the grade?" Simple. Anticipate what the teacher wants.

I've taken a exam. Challenged the teacher and won. Why? Teach said, "Your not supposed to know that yet." I also figured out how to be a ghost in classes ad I got "If you have better things to do, don't bother coming to class!"

We'll figure it out.

==
 
Hi John,
The British automobiles were not know for their robust electrical systems and you may not have much to work with but the folks on this forum have always been helpful for me. Let me attempt to be helpful here. Post #6 from Mike is perfect for this arrangement. Lets start with the relay connections and define. The #'s 30 -85-86-87 and 87a are a common Bosch relay configuration and the terminals are marked on the relay itself. I don't know what the Jag uses for relays but the principle is the same. Mikes diagram shows terminal #30 as B+ to the motor on one relay and the negative or ground to the motor on the other. Both of the 87a terminals are connected to chassis ground and when the switch is in the center position the window motor has ground at both sides of the motor and does not energize. Both of the terminal 87 contacts are connected to B+. When the right relay coil is energized via terminals 85 & 86 the normally closed contact opens and connects to terminal 87 to 30 applying B+ to the + side of the motor. It is grounded via the normally closed contacts on the left relay and the window goes up. When the left relay coil is energized the normally closed contact opens and connects terminals 87 to 30 applying B+ to the negative side of the motor and the + side of the motor is grounded through the normally closed contacts on the right relay reversing the polarity and the window goes down.

Mikes diagram shows the switch controlling the ground or negative side of the relay. This is common in most modern vehicles but the coil can be energized by controlling either side it really makes no difference.

I doubt the Jag uses Bosch relays but most relays have a legend printed onto the case that shows the pin-out of the relay and internal workings. Some relays have a diode (1n4001) built in and these are to control inductive spikes when the coil is deenergized.

I would recommend trying to wire one pair of relays per Mikes diagram and control the coil with jumper wires. Once 1/2 of the system is correct the other 1/2 is a cake walk.

Hope this helps.
rfranzk.
 
Hi All,
Just thought of something else. Most window motors don't use limit switches but they do have internal thermal circuit breakers that open if the motor draws too much current due to a stall or reaching the end of its travel one way or the other. These will cool and reset once the excess current is removed. I would expect the Jag to have this also but can't say for sure.

I too watched the Apollo launch live!! Probably a geezer.

Thanks.
rfranzk.
 
I want to add a few things:

1. It's always a good idea to add a diode across the coil, close to the coil. When the magnetic field collapses, a spike of the same polarity as the coil voltage is induced. A diode that normally does not conduct (The band toward positive) and connected to ground suprrsses this.

This is an aside, meaning not directly related)
2. In general, there are two ways to control a simple motor
a) The use of two signals Direction and (NOT Enable)
The reasoning behind using NOT ENABLE is so the motors don't move on power up, since most micros configure ports initially as inputs or an open circuit.
b) The use of two signals of Forward and Reverse.

3. In more complex, but simple control, there is fwd, rev, brake and coast.

4. You also have the choice of using power to switch something or ground doing the switching. At one time, a "high side driver" was difficult.

5. The 1965 Ford I owned switched positive at the door for the dome lamp. The Chryslers, Plymouth;s and Chevrolets switched ground.

While we are talking about different electrical systems, one foreign vehicle I owned had a fuse for low, high and for each bulb. The Ford in 1965 had a thermal breaker in the headlamp switch. One day when I was driving home, the headlights started to "blink". One bulb failed shorted.
 
Heres some pictures of a Ford electric window switch assy. This is common with these types of units that switch the actual motor current. The small amount of burning is enough to stop them working. These switches are expensive & getting hard to get, I repair them for people.
AU SW.1.JPG
AU SW.6.JPG
AU SW.7.JPG
AU SW.8.JPG
AU SW.9.JPG
 
I had to replace one in a 2000 Impala. That car has had a lot of annoying electrical problems which I think were water related. GM designed a <$5.00 piece of plastic that goes over the cabin air filter that prevents water from entering the passenger compartment and didn't tell the owners. "Me thinks" that the limits are handled with current sensing in the BCM (Body Control Module) and therefore it can handle auto-down for the driver's door. The top switch BTW is "window lock", all individual controls but the driver's gets disabled.

Is this really a common type of problem where someone could design an H-bridge type of circuit with a processor that uses current sensing, and the standard switches like debe posted and possibly make a profit?
 
Observation:

The initial window diagram shows motors with THREE leads. The ground is hidden. Does the Jag actually use two leads for the motor or three?

I have been assuming a two lead motor where you reverse the polarity to change the direction. If this has Ford origins, you could very well have an UP winding and a Down winding. UP/DOWN is useful if there are limits built into the motor. A single winding is useful because it uses less iron

In page 614 of the reference supplied by cowboy bob suggests that the connections to the motor are reversed to change the direction. UNFORTUNATELY, the OP's original post uses the two winding method to control the windows.

The methods are then Apples and Oranges.

I'd like to ask if the windows had the same amount of force with the original modification?
 
Yes, there are only two wires (leads) from each motor NOT three. To move the windows using the car's battery, you apply a wire from the positive terminal of the battery to one of the leads and a wire from the negative side of the battery to the other lead. If the window goes up, and you want the windows to go down, you just reverse the leads. With this said, are you saying Kiss that Mike's diagram is now not the answer.

On Mike's diagram he uses the numbers 80, 86, 87, 87a and 88. Bosch relays use 85, 86, 87, and 30. Thanks for clarifying things rfranzk and thanks for your explanation of the diagram. It really helped.

So let me see if I am reading Mike's diagram correctly. I hook the positive (red) wire from the motor to pin 30 on the right relay and the negative wire (green) from the motor to pin 30 on the left relay. (I don't know if the red and green wires are "positive" and "negative". I am assuming red is positive; so green must be negative.) A wire from pin 87 on each relay runs to 12 volts + dc and a wire from pin 86 on each relay is connected to each wire from pin 87 from each relay running to 12 volts + dc so each also is 12 volts + dc.

Pin 85 on each relay goes to ground and to one side of the switch. Pin 87a on each relay runs to the other side of the switch on each relay.

Did I get that right?

Thanks.
John
 
Hi John,

You are close. Terminal 87a needs to have ground to each relay so the normally closed contacts provide a return path for which ever direction is used. Terminal 85 and 86 energize the coil of the relay so you need to provide B+ to 86 of each relay and the switch will have a ground to be switched, then one side of the switch goes to terminal 85 of one relay and the other side of the switch goes to terminal 85 of the other relay.

Try wiring up the load side of the relay first and experiment energizing the coil of the relay with jumper wires, then the control side (switched coil) should be fairly evident.

rfranzk.
 
Hi John,

One more thing. The B+ connected to terminal 87 of the relays is typically fused and direct from battery, ie no ignition on required. The + voltage to the coil or terminal #86 is fused with ignition on control so the windows only function when the ignition is on. Later model vehicles use either a relay or a BCM (Body control module) to allow the windows to be operated with ignition off until a door is opened with disables their function.

Good luck,
rfranzk.
 
Since I had trouble following, I'll attempt a different explanation.

The relay is SPDT and has a Common NO (Normally open) and NC (Normally Closed contact) and a coil.

Each side of the motor connects to the respective relay common terminal.

The normally closed contact of the relay goes to ground. The Normally OPEN contact goes to a fused source of +12 (IGN usually).

So, now the deal is that one relay or the other is engaged and the motor travels in the UP or DOWN direction. If incorrect, swap the wires going to the motor on the motor or relays or on the switch below.

==
All you need is an SPDT switch or one side of a DPDT switch, center off, momentary in both directions:

a...x
b...x
c...x

on the back. The switch connects a to b or c to b.

We can chose to power the relays with a contact closure to ground or a contact to +12 (control). I'll chose +12 (control). This means that one side of each coil would go to ground. This +12 control source also can be connected to battery if you want the windows to operate all the time or to IGN+12 if you need to have the ignition on. The windows operating only with the ignition on, is likely a safety feature for unattended kids.

The switch would be wired with +12 (control) to the b contact and the other end of the relays coils to a and c. If the direction is wrong, you can also swap a and c.

So, motor power can be battery or IGN. For the windows to work with the ignition off, both the +12 control and +12 motor power must be from the battery.
==
I did not relate the terminal numbers to the coil, NO, C and NC contacts.
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To really finish it up, a 1N4004 diode should be placed across the coils and near the coils, with the band facing +12.

==
You can do all of your troubeshhoting with a meter before making the motor connections or a 2 lead bicolor LED and a resistor around <= 12/20E-3 ohms. 12 V divided by 20 ma. You should see a polarity reversal. You could also use two standard LEDs, two resistors and two diodes if you want for troubleshooting.
 
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As a follow up, my memory was correct in that I do not get any clicking when I use the 6 pin DPDT switches. I even tried using the wiring method set forth at https://www.robotroom.com/DPDT-Bidirectional-Motor-Switch.html. So the windows have never moved at all with the 6 pin DPDT switches. These are the switches that I know are rated for 30 amps. I purchased them from www.delcity.com, an Oklahoma based supplier with a good reputation.

Today, I am going to try to wire up Mike's diagram. I hope this setup works. The only problem I see with it is that it requires two bosch relays per window. I have four windows, that makes 8 relays. I had a hard time finding a place to put the four relays I used in posting 1. I will be pressed to find a spot for 8 relays.
 
Put the relays in the door. Pin #86 should probably go to +12 IGN for safety's sake; although I seem to remember in the literature that CBB supplied, that there is a relay that turns power on, so your probably good.
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If your not using it already, the relay with the mounting tab and connector makes life a bit easier. https://www.delcity.net/store/Relay-&-Socket-Harness-Kit/p_72563

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This https://www.delcity.net/store/Non!illuminated-Surf-N-Turf-Rocker-Switches/p_788901.h_788938.t_1 DPDP (on)-off-(on) switch would probably be suitable. Note the 21 A @ 14 VDC rating and the different ratings for AC.
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Good luck!

Edit: added relay w/ connctor
 
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I did a quick wiring of Mike's diagram for the driver's window and the window went up and down up using jumper wires!!!!!!!!!!! Question: Can I use the two relays I used today for the driver's window for the driver's window and the driver side rear window and two for the passenger window and passenger side rear window? I realize if I do that I won't be able to move any two windows sharing the same two relays but its a help with the location problem that arises with the extra four relays. As far as putting them in the door, I see two issues with that. They can be exposed to the elements if you get rain entering the door compartment first and second I have to run five 10 gauge wires through the door jam. That second one is a big issue. Even if I use 12 gauge wire, five strands of 12 gauge wire is bulky and going through the door jam usually means drilling new holes in the car that could lead to leaks. But if I can use two relays for two windows, then I get away with using four relays and I can keep the four where I currently have them. Hey but this is a problem I don't mind having. Mike's setup is working. Now I just have to implement it. I have several great minds on this website who can easily help me do that in the most effective way. (Yes Kiss, I am using the relays with the connectors. They are great. Thanks though for the url.)
 
Where do yo get 5 #10's. You really only need two. Power and ground. All the others should be in the door. A bond wire is all you need for ground. Assuming the window switches are in the door. The control wires (coil) could be 22 AWG, but I would not use anything less than #16.

Door mounting is not a problem with wires down.

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There MIGHT be a way to do UP/DOWN and select using 6 relays. Switches would have to be DPDT though. But then total independence would not be possibe. 1-4 up or 1-4 down would be possibe, just not at the same time.

The door would need power/ground. The drivers door would need 6 (up/dn) ) 3 small wires.

Again assumes window switch on door.
 
The switches in this car all are located in the console between the front bucket seats. But I tried the system using the four relays I already have installed (2 for the two driver side windows and 2 for the 2 passenger side windows and it worked great. No independent on each side but that is fine with me.
So looks like you all have solved my problem. My hat off to you many times with much thanks!!!!!!
 
Great your happy an thanks for thanking all of us.

==

FWIW: I used a Bosch relay for an alarm starter disable in the engine compartment. I also used them when I installed power door locks using a solenoid and not a motor. I think I put the relays in the door. I did add a switch that selected driver or all doors. Again, FWIW, in the vehicle I owned, I was able to install a microswitch that would set off the alarm when the door handle was tried. Alarms didn;t help when it was blaring and I someone just lifted stuff from my trunk and I saw them do it.
 
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