Help needed on a DEC LA180 printer

Hi! I'm a Computer collector from Germany and the last 3 years i spend a lot of time in reconstructing and repairing my PDP11/05 along with its peripheral devices (2x RK05,RX02,BA11ES). Noe that these things are working im trying to repair my LA180-PD printer, that was in no good condition. With a copy of the logic-prints i was able to find some faulty IC's on th logic board- but there must be at least one more. On Power-Up the carriage starts to move back to left edge but stopps before reaching the left end then the bell is turned on permanently. There is no reaction on any button pressed or switched over. Unfortunately i have no Maintenance Manual or Logic description, maybe there is a person out on this list who can help me with a copy of the documents. Regards Axel Harten.