Check the ECU documentation for CANH and CANL wires on the pinout diagram.
Connect CANH and CANL from the ECU to the corresponding pins on the Dash using a twisted wires.
In the Haltech ESP software press F4 to open Main Setup.
Choose “Devices” – “OBDII”, change to Enabled.
Also make sure in the field above you have chosen the correct can bus port.
In the dash configuration software choose ECU > OBD.