%Left Margin Drifting ProblemLeft Margin Drifting ProblemNOTE:This information is also provided in Technical Service Bulletin 1707.To correct a problem with the left margin drifting during print operations, follow this procedure.1. Manually slide the carriage assembly back and forth along the full length of the carriage shaft.Check for "drag" caused by the ribbon, a dirty space rack, or other obstructions.If you suspect that the ribbon is causing movement problems, check the movement of the carriageassembly with the ribbon removedOR with a new ribbon installed.2. Check the contact between the carriage frame and the space motor board assembly.Contact is made at the front edge of the board.Any gap will keep the space motor gear from fully engaging with the space rack. This will result inslippage problems, which will affect spacing operations.3. Check the printhead cable connections between the main control board and the space motor.Solid contactMUST BE made at all connections or print problems will occur.4. Check the condition of the printhead cable. If it is broken, torn, or sharply bent, replace the cable.5. If the problem continues, check the parts listed below (in the order given). Replace the suspectedpart. Be sure to test the printer after replacing each part.1. Carriage: Frame Set2. Motor: Space3. Rack: Space4. Cable: Printhead5. Board: Main Control6. If the problem continues, check all assemblies and connections. Then, contact Okidata TechnicalInformation for further assistance.ML520/521 ( 96-02-04 )