Install Series Damping Resistors on SPI Clock Lines

If wiring shortening and shielding have not resolved the SPI errors, signal ringing due to wire inductance may be causing bit-flipping. Follow these steps to damp the signal:

1. Identify the SCK (Clock) line on the encoder harness, ideally as close to the VESC controller's input pin as possible.
2. Solder a small surface-mount or through-hole resistor (between 22Ω and 47Ω) in series with the SCK line.
3. Ensure the resistor is properly insulated with heat-shrink tubing to prevent accidental shorts against other pins or the controller chassis.
4. Reconnect the encoder and use the VESC Tool Terminal to monitor for persistent FAULT_CODE_ENCODER_SPI errors while the motor is under load.
5. If errors persist, verify that the encoder is powered by the VESC's 3.3V logic rail rather than the 5V rail to further reduce noise sensitivity.

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