Automobile Power Folding Mirrors

[BoyWonder]

Hi, I got redirected to this forum who doesn't help with this kind of project. I am an amateur so and appreciate any help I can get.
I am working on a my car which is a hobby of mine. I have decided to install power folding mirrors. I have done this on one of my previous cars which was pretty simple, however with my car now, which is way more advance, I am tackling this project. I have a couple friends helping me and I am looking for other help/assistance/advice. So here goes...

I am tackling this project using the OEM power folding switch which is a simple push button switch. The mirrors work on reverse polarity so all the switch is essentially doing is bringing the power to ground. The challenge is I have to make my own harness. I have come a long way since I have started this and am about half way to success. I am at the point where I can get the mirrors to fold in, however I cannot get them to fold out without manually reversing polarity. I have a couple friends helping me and have a circuit diagram that is the closest thing I have had to get working. I am looking for any assistance or advice. Things to change or test. Here is the diagram;

3x Auto Relay
2x 10K Resistor
1x 100K Resistor
NPN Transistor (4401)
Toggle Flip Flop (NTE) 754

I am using ACC (12V) for my power. I have an Alligator clip clipped on to my ground. The wire labeled Pin 9 is what is going to go to the switch. For testing purposes, I simply apply that wire to ground and the mirrors fold in and release the wire when the motion is complete. The outcome I'm looking for is if I was to push the button again, the polarity reverses and the windows fold open, however this is where I am stuck and nothing happens.

Can anyone help me in terms of the circuit and tell me if this is close to my desired outcome? Any input?

 

[BoyWonder]

Anyone have any input or help at all? I basically need a circuit that will reverse polarity using a simple push button switch. I tried using an online circuit builder but none of them have all the parts I need.

 

[Cicero]

Could you not just use a single DPDT relay for this? That'll easily switch your polarities.

Im not sure why you would want a non latching push button though? My car has folding mirrors and when my switch is in they fold in, when its out the mirrors are out.

 

[alec_t]

One problem with your circuit will be the continuous current drain by the K3 coil when the latch output is high.
Couldn't you just use a double-pole double-throw switch?

 

[BoyWonder]

Could you not just use a single DPDT relay for this? That'll easily switch your polarities.

Im not sure why you would want a non latching push button though? My car has folding mirrors and when my switch is in they fold in, when its out the mirrors are out.

I know what you mean. My other car has this type of switch. The problem is the OEM switch on this car does not work like that. The switch is a simple switch that connects 12V to ground and disconnects when I release, by design. So when I push and hold the button, the mirrors will fold in and I will have to release when the fold motion is complete. Not really how it should work but my main objective is to keep the OEM switch as I have no place to mount an aftermarket switch.

One problem with your circuit will be the continuous current drain by the K3 coil when the latch output is high.
Couldn't you just use a double-pole double-throw switch?

This is my second attempt at a harness. My first attempt that I found online used 2 DPDT relays which I built but that did not work at all. Here is that circuit;

This would be an easy project except for the fact that 1) my button is a simple push button and 2) the mirrors work on reverse polarity. I am not savy enough to figure out what circuit I need to build.

 

[alec_t]

I don't see any limit switches in your circuits. Do the motors have built-in overload protection? If not, how do you plan to prevent motor burn-out if the OEM switch is held down too long?

 

[BoyWonder]

I don't see any limit switches in your circuits. Do the motors have built-in overload protection? If not, how do you plan to prevent motor burn-out if the OEM switch is held down too long?

Yes, they are built in

 

[cowboybob]

Didn't know they had limit switches. That's very good. In that case:

This works:

Obviously, two reversal relays and mirror motors are required.

Best to fold mirrors "in" before turning off the car so that when the car is powered up, pushing the "button will fold them out.

 

[BoyWonder]

Can you repost your image, or is there another reason why I don't see it? I only see a broken image link

 

[cowboybob]

Redone a bit: don't see a need for two reversal relays. Of course, that doesn't mean two can't be used. Again, assuming limit switches in each mirror motor circuits.

This circuit powers up with CW motor rotation. So wire the motors with that in mind, i.e., ignition "on" with presumed "folded in" mirror's position allowing a momentary button press to "unfold" the mirrors:

Another button press will force the mirrors to fold in.

Note that no current flows when ignition is off.

 

[KeepItSimpleStupid]

Alec:

Isn't this the SAME or VERY SIMILAR problem we attempted to solve here?: https://www.electro-tech-online.com/threads/need-help-with-simple-i-hope-auto-circuit.143370/

The only real question is does engine OFF mean reset to fold or reset to open or does it keep the same state between engine re-starts?

PS: I actually ordered a couple of the ELM411's to play with. I seem to remember a folding mirror thread years ago on ETO.

 

[alec_t]

KISS:
The only similarity seems to be that a toggle action is required? Here, it is arguably less critical what the toggle default state is.

 

[cowboybob]

I just realized that my circuit fails to include the limit switches.

I will post a revised schematic (and then remove the ones in error above).

 

[cowboybob]

BoyWonder, is simply reversing the polarity enough to make the mirror assemblies perform correctly, i.e., stop when fully open or closed, even if power is still applied to those assemblies (as is the case with my circuit if the ignition is on)?

Here's an example factory F150 folding mirror schematic:

Note that limit switch(s) condition(s) are handled external to the mirror assemblies.

 

[BoyWonder]

I've been testing and decided that I am going to try to build again from the ground up. I thought I was close but not sure how close I really was haha.