The 32 pin connector enterring the prius inverter will be intercepted by the new conversion board. Another 32 pin connector will connect the new board to the inverter.
The male 32-pin connector that is attached to the hybrid ECU is number: 1318747-1 The female 32-pin connector that is attached to the inverter is number: 1318745-2
Fig 1.1 The 32-pin connector to the main board
Interceptions can be made using an analog multiplexer chip like the 405x family of chips. There are 4 pins that need to be intercepted:
There are 6 sensor pins that need to be monitored:
And 5 error pins that need to be monitored:
There are also 2 ground pins:
[Which ground should I use? Probably boost converter - can they be connected together?]
The board must be able to control 2 sets of contactors:
The High Voltage Battery has 3 contactors in the System Main Relay unit, as seen in Fig 2.1. These three contactors are controlled by the Hybrid Vehicle Control ECU at pins CON1, CON2 and CON3. This must also be intercepted by converter board.
Fig 2.1 The High Voltage Battery contactor arrangement. The orange wires are the positive and negative terminals from the battery. You may notice that the positive wire has 2 contactors, 1 for precharge through a resistor and 1 without the precharge resistor.
Two contactors will also need to be added in order to connect and disconnect a motor and to connect the mains to the inverter also.
Digital pins: 12 Analog pins: 6
Analog pins can be reused as digital pins.