Check out the pic, it's from a JDM blower the loose pin is the ground and it from the left or right corner (depends how u look at it)

The blue wire is power from the JB and the red white wire in the middle is from the AC control ECU, I guess it sends different voltages down this wire to determine the speed.

 

I think these are your three wires:

 

C-17 (3) is to a constant +12v

C-18 (28) is a switched +12v

 

without a JDM blower you might have to come up with your own pulse controller solution.

 

Oh, I do have a JDM one. I have the US one back in the car because I needed something to move air to defrost my windows lol

 

NVM Then lol

 

I always wanted to do this since moving to the US and realizing that they like to take out standard options on the Japanese models because they don't think people in the US would pay for them. Kinda annoying, even my '99 VI GSR had auto climate control and outside temperature!

The price on all those parts new seems excessive though, are there any places in the US that bring in half cuts (mostly for the engines) that you could get all of this out of cheap?

 

The 6 wires could be the ones surround the "J/B" in the picture i posted then.

NVM ^^^ doesnt make much sense. Its kinda hard to figure out whats what from the diagram without having the physical stuff too.

 

The 6 pin plug refers to C-28, only 3 pins used, pin 6, is the blue wire going to the JB for power, pin 3 is the black wire going to a ground, finally Pin 5 is the red white wire coming from the A/C ECU C-17 pin 2.

I guess this wire sends a different voltage to speed up and slow down the blower, bit like resister but with more speed options.

 

I'll have to look at it again with the blower out of the car. I also don't have plug C-28 so I've ghetto-rigged it with female spade terminals. Problem I was having is the fuse was blowing. Maybe it was the plugs somehow shorting from touching? But they're all heat-shinked and shouldn't be doing that.

Anyways for now I've re-wired the USDM blower motor back in with just the fan speed control so that I have defrost and heat

 

so if the blower housing takes 3 wires then it would have to be +12v, ground, and PWM signal from the AC ECU. Which would mean the controller is built in. Using that picture unihappytime posted you should be able to figure out which pin is the pwm

 

correct; i basically wanted to confirm what i was thinking

My biggest confusion is that I didn't know the blower relay was "always hot" essentially so I was having troubles figuring out what wire was signaling that relay to activate

So correct, C-28 (3) on the blower is ground, C-28 (6) is power from the relay, C-28 (5) is the signal from the A/C ECU C-17(2)

 

for my arduino approach im going to basically wire up a speed controller from amazon or something and use that to control the factory 2 wire from one of the arduino pwm outputs. I was tossing the idea of actually using a boost converter to pump some extra voltage into the fan for higher speed, but i gotta finish the code for these actuators before adding more stuff to the dev list.

 

From all the work I've done, your approach may be FAR easier for future swaps. Swapping the Air Mix and Mode motors can all be done, with some contortionist difficulty, with the entire dash in place pretty easily

 

I think the blower relay is only activated when the keys are turned to 2 so it means the blower will only have power when the key are turned to ACC position?

After that the van speed is controlled by the ECU with the signal wire as opposed to the resister on our manual versions?

PS I have a JDM RS 7 so it came with state of the art manual AC