Lexmark T642 Service Manual - Page 127

4061-xx0 Fuser service checks 920.xx-Cold fuser service check Error codes 920.x and 922.xx may display for a cold fuser failure. Some 920.xx error codes may be cleared by turning the printer on and off and allowing it to complete POR. CAUTION: There is a danger from hazardous voltage in the area of the printer where you are working. Unplug the printer before you begin, or use caution if the printer must receive power in order to perform the task. Service tip: Some 920.xx errors can be caused by multiple sheets of paper being fed up to the fuser. Service tip: Set the Fuser Temperature to NORMAL before starting this service check. In Diagnostics mode, select EP SETUP, and Fuser Temp. Service tip: It may take several minutes for the error codes 920.xx and 922.xx to be displayed after the printer is turned on. FRU 1 Fuser lamp Fuser lamp AC cable 2 AC line voltage 3 LVPS 4 Fuser lamp Fuser top cover assembly Fuser connect cable (fuser to fuser lamp cable) Action Observe the lamp through the left near side of the printer. It may be necessary to remove the redrive assembly to observe the lamp turning on and off. If the lamp does not come on do the following: • If not previously removed, remove the redrive assembly. See "Redrive assembly removal" on page 4-74. • Remove the fuser assembly. See "Fuser assembly removal" on page 4-26. • Make sure the correct type of lamp is installed (voltage and wattage). • Verify that the fuser to fuser lamp cable is installed correctly to the fuser top cover assembly. If incorrect, install correctly; if correct, go to step 2. CAUTION: When taking measurements for AC power, observe all safety precautions. Check the AC line voltage to make sure it is within operating specification. If incorrect, inform the customer; if correct, go to step 3. CAUTION: When taking measurements for AC power, observe all safety precautions. Unplug the AC line cord from the printer and pull the LVPS out far enough to access CN1 on the LVPS board (see "Low voltage power supply removal" on page 4-54). Disconnect the LVPS to fuser AC cable, plug in the line cord, turn the printer on and measure the voltage between CN1-1 and CN1-3 on the connector (see the connector locations at "Low voltage power supply" on page 5-10). If incorrect, replace the LVPS assembly (see "Low voltage power supply removal" on page 4-54); if correct, go to step 4. Check continuity of the fuser to fuser AC cable, fuser top cover assembly, and fuser lamp by checking the continuity between the two pins on the fuser lamp AC cable connector: • If there is continuity, go to step 5. • If there is no continuity, check the continuity of the fuser to fuser lamp AC cable. If incorrect, replace the lamp, if incorrect, replace the fuser top cover assembly. Note: If the fuser lamp is replaced, allow the fuser assembly to cool or a 925.xx error may be displayed. Diagnostic information 2-87