HV fan blower wiring

Can anyone help with the wiring of the HV blower fan? I purchased a Russian made grid charger designed for the Honda hybrids but with adaptable settings that allow it to be programmed for the Prius.

I have used it for charging and discharging and it works well. But, it has a harness to operate the HV blower fan when a temp sensor reaches a threshold temperature. I installed all the harnesses and placed the temp sensor on the top of the middle battery modules.

The maker of the grid charger has reviewed the Prius wiring schematic I sent him and he and I agreed on where to splice into the Prius wiring in order for his blower harness to operate the Prius fan. His charger has built-in PWM circuitry.

His battery fan output connector has 3 terminals:

12V
GND
SI

I connected his terminals to the following wires in the HV blower fan wiring harness on the right side of the rear compartment near the fan:

12V to the light green wire
GND to the white/black stripe wire
SI to the yellow wire

Oddly, when the grid charger activates the fan I am only seening 150mV output on the 12V terminal/line. Other than an internal problem with the Grid Charger is there any other thoughts/ideas?

I have attached a colored schematic as well as another image I found online with a short explanation of the Prius fan wiring. I would appreciate any helpful ideas.

Paul.

 

Bump. Anyone out there who still has a lot of wiring experience with the Gen2 Prius HV battery blower fan?

Paul

 

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The connection on the HV fan is a 2-pin connection. The wiring going to the fan has 2 light-green wires attached to one terminal, 2 violet wires to the other. The light green is the 12V or B+ line. The violet is designated VM. I believe this is a voltage monitoring line for the battery controller unit.

This is controllable by setting parameters on this grid charger. So, I could easily set it to run at 100%. This grid charger triggers the HV cooling fan when its temp sensor (which I placed on the top of the battery modules during my harness installation) is within 5C of a preset temp. Once the temp rises to the preset temp then the fan is supplied full 12V power via the grid charger's intermal PWM circuitry.

.... or at least in theory. Since I am only seeing 0.15V on the grid charger's fan control harness I am concerned there could be an internal circuit issue on the grid charger. Or, I need to adjust my wiring scheme. I am leaning toward a grid charger internal issue at this point.

I am running an external fan that I have routed to push air through the Prius HV air cooling pathway. But, for future reconditioning I would prefer to work everything out and not have to pull panels to access the HV battery ductwork.

 

Source was google. But, this colored schematic matches all the other schematics for these circuits. The colors simply make it easier to identify wires so I preferred this one.

Paul

 

Google was _my_ source I have no idea who the original author is. But, I do believe there are color european schematics so maybe the source is actually Toyota??

Actually all 4 wires do go to the fan. Here's a pic where you can see the wires at the connector. And, this matches the schematic...


Paul.

 

What I am struggling with is learning enough about the PWM circuitry to be 100% positive that the advice given to wire up this grid charger to the fan is correct. While this charger is primarily made for the Honda crowd it has enough setting options to be set to work very similar to the Prolong set up. I believe I have the wiring done correctly so the fact that the voltage to the fan is only reading 0.15V makes me think something is wrong with a component on the charger's circuit board.

I am on my final soak charge. I didn't go fully with the Hybrid Automotive discharge voltages (134, 84, 17). Instead I went with 177, 100, 34. I suppose for future reconditioning I can rig up a small fan to the HV battery duct inlet in the back seat if I cannot get the grid charger to operate the fan properly.


Paul