Manually command a 12V solenoid PWM - High Side

Using Arduino Project Guidance
1

Hi everyone!
Well I am new to the forums, arduino and programming etc, but ready to learn.
I come here as I know the versatility of these little boards and all other routes have fizzled out.

Let me start with what I am trying to accomplish:
Mimic the function of an existing PWM circuit controlling a solenoid inside a transmission.
Operation: 12V (14V running) @ fixed 50Hz, PWM controlled where 95% duty cycle = 0.95 A.
12.6 Ohms across the solenoid and circuit.

*One very important characteristic of this circuit is it has to be high side switched.
There is no access to the ground side of this solenoid, it is grounded inside the transmission.
I am definitely not about to tear into it just so I can get access to the ground wire.
This is the one thing that has been the big hang up.

Currently the transmission controller obviously tells this particular solenoid how to operate.
The higher the duty cycle the more hydraulic pressure and lockup there is.
I would like to use an Arduino and other necessarily hardware to manually command a PWM (0-100%) with a POT.
This would be the sole purpose of the Arduino.
What I would like to do is be able to switch to manual control for short periods.

I would like to know if this is at all feasible and what hardware I would need to start this project.
From the little I have taken in thus far on the Arduino, I know they can't directly control the solenoid.

This video is basically what I am trying to accomplish.

But once again the circuit I need to make has to be high side switched.

Can this be done?
Any help would be greatly appreciated!
Thanks

2

I think you have two problems to solve. One is switching between the original controller and your Arduino control - have you a plan for this?

For high-side PWM you need a PNP or P-channel switching transistor that can handle the currents, the obligatory flyback diode, and something like a small-signal NPN transistor to level-shift the 5V Arduino signal to drive the high-side device.

3

Rugged Circuits has lots of basic and not so basic circuit designs on their site. Here is 'high side' switch:

http://ruggedcircuits.com/html/circuit__19.html

4

This is definitely the place to get this problem solved!

Yes you are correct Mark I do have plan to switch between the two, as well as a dummy load for the TCU as to not throw any trouble codes or go into limp mode.

Thank you for the link retrolefty, I scoured the internet as much as I could to find such a schematic but had no luck.

5

Any recommendations as to what model Arduino would work best for this?
I am thinking the Uno but would like to hear some input.