开云体育

The 2 check LED’s deal with the state of the instrument and the communications between the upper and lower units. If the upper unit does not power up but the bottom unit does, IIRC the right LED will be on. If the left LED is on the typical cause is a stuck key on either unit. The simplest test for this is do a key press on every key, if no movement the key spring is loose in the unit somewhere, probably just behind the keyboard, but it can be anywhere in the unit. You can pull the key(s) to the out position
and do the IP and it may clear it. A little tape can be used to hold the key in the open position temporarily.

Don Bitters

Also, I have seen the intermittent caused by an intermittent interconnect cable on the rear. Usually a broken wire inside the connector from cable stress or worst case where the cable meets the connector shell. Those are still repairable, but harder to do. (Find the broken wire, slit the plastic sheath, spread the wire sheath, find the break, repair or jumper it, insulate the single wire, put it all back inside the sheaths, tape up the slotted plastic sheath, check the cable continuity.) Doable, but a PITA. A replacement used cable is in the $35 to $150 range on EBay.

Don Bitters