Planning to finally install my harness into my car this weekend, I had been watching various videos of commercial harness installs(ha & maxx volts) and noticed a fuse installed neat the negative connection.
Got the harness installed today, tested the fan control and was able to adjust the speed without any issues. Also read out the battery voltage (174v).
Did not begin any charging yet need to find a stretch of days to take it off the road.
However I did notice that the fan is running constantly at the set duty cycle of the controller. The diode is wired in line with the 12v supply from the controller, maybe it could not handle the current and is already shorted. I guess a relay would be a safe bet but I'll need to wait for one. Did not get time to diagnose it today. If that diode failed I may try two in parallel.
Before you get too crazy with it, I would just try a simple grid charge sufficient to input 6875mAh (8800 preferred) and assess the performance. Have you checked the tap voltages? Are you dealing with a P0A7F, or do you have other codes?
There have been instances of full blast fan operation following the installation of the maxx volts chargers even after harness removal. If the diode shorted, I would expect this operation, not that it runs at whatever speed at which the controller is set. A wiring diagram would help.
I have not checked with an odb reader but I seen no check engine light.
I'm not sure what "check the tap voltages" means but I have readout the battery voltage using the power supply volt display. 174v was the reading with a full 8 bars on the SOC in car indicator.
I have drawn a schematic of the harness below. I could keep it as is but the fan at 50% is pretty loud, I can't say that I ever heard the fan on with normal driving(its not hot here in Ireland). I can access the controller easily as it's tucked in at the left side of the battery compartment.
Once I at least have a look at the controller while the car is running will tell me of its getting power.
The full charge will be at earliest this weekend due to a need for the car.
FYI I used a crude mosfet diode as an icon for the fan controller.
Harness schematic
Last edited by Kevinmce; Jan 28, 2019 at 02:27 PM.
Probing the back of the above connector (where the wires go into it, do not unplug) will give you the 11 tap voltages the car monitors for battery health. Each measurement is 12 of the 132 cells.
I have not checked with an odb reader but I seen no check engine light.
I'm not sure what "check the tap voltages" means but I have readout the battery voltage using the power supply volt display. 174v was the reading with a full 8 bars on the SOC in car indicator.
I have drawn a schematic of the harness below. I could keep it as is but the fan at 50% is pretty loud, I can't say that I ever heard the fan on with normal driving(its not hot here in Ireland). I can access the controller easily as it's tucked in at the left side of the battery compartment.
Once I at least have a look at the controller while the car is running will tell me of its getting power.
The full charge will be at earliest this weekend due to a need for the car.
FYI I used a crude mosfet diode as an icon for the fan controller.
Harness schematic
Okay... First, if the controller isn't getting power, it shouldn't be sending a signal and you shouldn't be able to adjust the fan speed when the separate 12V PSU isn't driving the fan/signal generator. It sounds like you may have indeed shorted the diode.
The only risk associated with running the fan at 50% all the time is burning out the blower... but... you're likely to extend the life of the battery as heat and hot-spots due to insufficient cooling are key factors in poor longevity.
For simplicity, the signal generator shouldn't be in the harness but in the charger, i.e., when you disconnect the charger, the signal generator is disconnected as well.
I forgot you were at the stage of recals and had not yet generated a code. It's worth putting it on charge even just overnight to see if the recals decrease.
Indeed I intended to have the signal generator in the charger but I forgot I needed 5 core for when buying the cable. Ended up with a 4 core and tried to create a workaround.
I may just go buy a 5 core wire, wish I did that before installing the harness
But on the bright side I was able to install the complete harness without removing the IPU or the battery. So should be an easy replacement. Will just need to redo the connectors and fuse.
Confirmed today that the pwm generator is indeed getting power when the car is started, so the diode is probably shorted.
Looking at my options I've opted for trying a standard automotive relay, it will be less effort for now. I'll at least get it in and tested this week and hopfully move onto my first charge/discharge cycles next weekend.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Re: Building a HCHII grid charger
