Hey all, I don't have a Prius, but I'm using a gen3 Prius inverter pump to circulate coolant in an air to water intercooler on my JDM Toyota Vitz (using JDM ST185 Celica GT4 air/water intercooler, custom lines and radiator). See picture of wiring diagram for pump below. Relevant points: 1. Right now the pump is pulsing, but from what I've read online it should be running constantly. Is this correct? 2. Currently I have GND (white-black) hooked up to chassis ground and +BWP (blue) to 12v via a relay I installed (when ignition switch is on it sends 12v to this wire). 3. NWP (pink) wire appears to be some kind of signal for the ECU (to know it's running) - this should be irrelevant for my purpose, as it's not in a Prius! 4. SWP (green) wire appears to be switched power? Do I need this wire also hooked to 12v for the pump to NOT pulse? 5. What am I missing? Perhaps the green wire is 12v and the blue is 5v? thank you!!
It is a variable speed pump. You need a 0-12v pulse waveform coming in on swp. Failsafe is 15% off 85% on. Speed will decrease as the on time is reduced.
Appreciate the response! Forgive my ignorance, but that means I can't just run 12v to SWP and have it run 100% of the time? Or would that burn the pump up? If not, is there a way to have it run 100% of the time easily? thank you!
See this post, which is about the engine water pump, but the control scheme is the same. In the tachometer signal coming back from the pump, shorter wavelength (higher frequency) corresponds to higher pump speed. In the how-fast-to-run signal sent to the pump, it's not the wavelength/frequency carrying the info. The duty cycle (how much of the wave period is spent high instead of low) is what indicates the speed wanted. The frequency / wavelength doesn't necessarily change at all. I measured steady 25 Hz on the output to the engine pump, or four 10 ms divisions on my scope. The picture in the manual for that also says "20 ms/div" like rj's picture, and still shows four divs as the wave period—which would be a frequency of 12½ Hz—but that wasn't what I saw for the engine pump and I suspect it's just a typo. I doubt the pump cares much about the frequency, within reason, as long as the duty cycle makes sense.
Wild so you're running a Celica all trac setup 3SGte the BEAMS? Seems to me any 12 volt water pump with 5/8 barbs would work well for you I found using an Italian 12-volt water pump It's a mag drive type unit used on a lot of Italian big bore scooters a 16-in wheel things a grown-ups drive in Europe A lot of those are water cooled I'm using one of those pumps and one of my Prius right now as the inverter pump just because I had it laying around and it was easy to wire up and has been running ever since and they're like $40 and they don't have any pulsing and waveform problems or any of that stuff or you could just try a generation 2 inverter cooling pump I think it just runs the one speed or whatever which may not be enough volume for you I don't know but the one from the scooter moves a bit more water than the generation too stock inverter pump. And is inexpensive and there's a bunch of them on the net.
haha I wish Beams! No this is a silly fun turbo project boosting 1.0 1szfe. I actually have a clone Bosch pump but I thought the Prius pump would be completely silent from the cabin. Seems I’ll have to switch back to that pump. I got this Prius pump for cheap and figure I’d give it a go, but should have read more about this pulsing business! I’ll wait before swapping back, to hear if there’s a simple way to get the Prius pump to run 100% of the time by giving voltage/grounding the pink wire. Eh?
I guess I'll swap back the other pump then? Unless anyone knows an easy way to get this pump to run 100% of the time.
According to Chapman the SWP input is already at 12v (via an internal pull-up resistor) even if it is not connected. You could check that with a meter. SWP should be pin 3. You could try 12v on the swp input pin 3. I would do nothing with pin 2. Otherwise you need a pwm generator capable of adjusting frequency and pulse duty cycle. If you want to experiment this $13 Amazon pwm controller might work.
The pwm controller seems pretty solid and has the ability to lock in the freq and duty cycle through a power fail.
