I have the service manual for the MCL system - it covers the type 2020 (not the 2026). Unfortunatley my scanner has stopped working and I could only try and take pictures of the diagrams with a camera! A quick look at the diagram and there should be 12v, 6 v and 5 v (for the microprocessor) outputs
(I found that the ribbon cable had separated (it looked okay) on mine and with a new pair of strips it worked again! )
Brian