Brakes - frk2/opencaret GitHub Wiki
Overview
The brake is going to be your next modification. The brake module for Kia SOUL EV Brake consists of two parts. The first part is the actual PDT and PDF signals spoof and the second part is the brake light switch.
Brake Pedal
To modify the brake pedal, we will disconnect the Brake pedal stroke sensor (1) and Stop light switch (2). We will spoof the signal between with the brake module.
Brake Module / Vehicle Control Module (VCM)
Since the brake on the Soul EV is regen brake and electronically controlled, we won't perform any modification similar to Soul Petrol. The VCM controls the open and closing stroke sensor for the braking as well with Normally Open (NO) and Normally Closed (NC) relays for the brake light switch.
Cable harness
Ballenger motorsports again, with these connectors:
Installation
- Step 1 Remove the brake pedal stroke sensor and stop light switch
- Step 2 Install the VCM Connector for the pedal stroke and stop light switch
Brake Pedal Pinout
As we see below, the VCM sends the PDT and PDF signals just to mimic the human pedal stroke. These are voltage controlled value. The Soul Brake pedal sends the command to the Integrated Braking Unit (IBAU) which sends the actual pressure (Pressure Sensor) to the brake solenoids.
Below is the Brake Pedal Pinout:
The schematic labels the pins when you are looking at the receptacle from the IBAU
Using the pin numbering on the connector itself and this becomes:
- Pin 1: GND
- Pin 2: GND
- Pin 3: 5V
- Pin 4: SIGA
- Pin 5: 5V
- Pin 6: SIGB
The color coding for the brake DID match the one on KIA Soul, so that is another way to check you have wired everything correctly.
Stop Lamp Switch
Bench testing
Brakes are hard to bench test but the theory of operation is similar to the throttle. Tested this in the car since taking the brake pedal out is quite a bit of work. So hook the pedal up to the oscc and provide it 5V and GND using the board and it should come to life. You should be able to use joystick commander to send a 'enable' to the brake and it should click. Measure the output voltages on the board to make sure they correspond to what the brake pedal outputs. These voltage ranges are documented on the OSCC wiki for reference.