UBI EasyCoder 501 – Service Manual19426. TROUBLE SHOOTING, cont'd.26.3Printing TroublesContinued!The best way to start is to get an overall check of the printing, whichis easily done by ordering a series of test labels to be printed in theTest Mode (see chapter 25) or in the Setup Mode (see TechnicalManual or Appendix 1).In case the printhead is suspected to be defect, it could be checkedby the following UBI Fingerprint instructions (see UBI FingerprintReference Manual):• FUNCTEST$ ("HEAD")• HEAD• SYSVAR (21|22)No printout at all• Are both cables between printhead and CPU board fitted correctlyand not broken or otherwise damaged? The flat cable from theinner connector on the printhead should run to P-700 and thethicker cable from the printhead's outer connector to P-301.• Is the printhead clean? Residue from label adhesive or burnttransfer ribbon on the printhead prevents it from functioningcorrectly. Clean as described in the User's Manual.• In case of direct thermal printing, verify that the stock of paper isintended for direct thermal printing (not thermal transfer!) and ofapproved quality.• In case of thermal transfer printing, check that the ribbon is ofapproved quality and fitted so it can move freely. The “ink”-coated side must be turned towards the paper.• Check that the printhead voltage, P24, is +24V ±1V whenmeasured between pins 1-5 and 6-10 of connector P-301 ortestpoint P24 (see chapter 17.7).• Check that the printhead is completely lowered and pressingagainst the paper web with a sufficient force, see chapter 24.3.• Check that the headlift sensor is in order, see “Printhead lift sensorout of order” in chapter 26.2.
