Seems like DC/DC converter on OLED board is faulty or microprocessor on OLED board (chip on glass - can not be replaced) is faulty and drain to much current. Please measure voltages on 2 DC/DC converters, I marked 10 points:
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UTCOMP-PRO_OLED-Voltages.jpg (195.52 KiB) Viewed 6388 times
Ok, it may be DC/DC converter faulty or driver on OLED. Please replace this chip marked with pins 6-10, it's MP1541 / MP1541DJ in SOT23-5 package: https://www.monolithicpower.com/en/mp1541.html
It can be short circuit on your wires or cable length - this element should be assembled onboard with as short wires as possible. Broken pin with ground can be soldered from other place.
Does UTCOMP is still working with other display? Because it seems like now UTCOMP is not giving voltage - it may be broken internal switching transistor. Please check it on ignition switch ON (on ignition switch OFF voltage is disabled)