Nissan leaf

This unit takes the 280-400VDC HV battery pack input and converts it to 13-15VDC for the 12V AUX battery charging. It is very stable at 74 Amps 13.6V output. Easily adjustable voltage output with a simple 10V PWM signal running at about 9 HZ on pin 1 and pin 3 and 11 go to +12V to enable.

When i googled around i noticed this particular DCDC is documented on various sites and videos, however not with schematics or wiring diagrams… I used some photos and wiring from here: http://myimiev.com/forum/viewtopic.php?t=4533 Starting with connection of the 12v positive terminal to battery And then GND the case back to battery negative terminal I connected HV directly to DCDC input wires.

wiring

Then referring to plugs F11 & F12 Terminal 3 and 11 would need +12v for Battery power supply Pin 1 needs a PWM signal 9Hz 50% duty to it

Well it was all good and well with the wiring obtained online, however i noticed that DCDC starts as soon as i provide 12V to pins 3 and 11 of connector and provides 14V power to charge 12V battery.

When i added 9Hz PWM to pin 1 of connector F11 i got following result: PWM voltage 80% 13,10V 70% 13,40V 60% 13,70V 50% 14,00V 40% 14,30V 30% 14,70V 20% 15,00V

If i remove PWM from pin 1 i again get 14V on DCDC output.

Also i tested the output with 14V 85A load (9x H4 light bulbs and 60Ah Pb battery) and DCDC provided true and steady 14V power.

CAN bus messages

A database of Nissan Leaf CAN Bus messages can be found here https://github.com/dalathegreat/leaf_can_bus_messages