JZS161 P1656 Oil Control Valve Circuit Malfunction

Hello everyone. Before getting my Aristo tuned, I’m addressing some issues typical of owning a 27-year-old car. During my setup with the ECU Black and the PNP harness to run the factory A340E transmission, I noticed a check engine light (CEL) for an oil control valve circuit malfunction (P1656).

I’ve checked the VVT-i sensor’s resistance (it’s within spec), cleaned the oil port filter, and even replaced the sensor to see if it would resolve the issue. This CEL only appears when the standalone ECU is connected.

Has anyone experienced this before? Can this be addressed through tuning, or is it a hardware issue?

Thank you

Update: I have posted images below that I taken. Ive discovered that the pnp harness doesnt have anything from the oem ecu outputs; which makes sense because the standalone is now controlling vvti. But I am assuming that the ecu doesnt like not seeing something there.

What do you think my next course of action should be? Resistor? Diode?