Keysight Technologies U1231A Service Manual

Contents

2 Service and Maintenance46 Keysight U1231A, U1232A, and U1233A Service GuideTroubleshootingIf the instrument fails to operate, check the batteries and the test leads. Replacethem if necessary. And if the instrument still does not function, check theoperating procedures in this manual. When servicing, use only the specifiedreplacement parts.The table below will assist you in identifying some basic malfunctions.WARNING To avoid electrical shock, do not perform any service unless you are qualifiedto do so.Table 2-1 Operating checklistMal function IdentificationNo display when powered ON using the rotaryswitch ✔ Verify the batteries health and replace batteries as necessary.No beeper tone ✔ Verify that the beeper is enabled in the multimeter’s Setup mode.Failed on current measurement (U1232A orU1233A models only)✔ Verify the fuses health and replace the fuses as necessary (see “Checkingthe Fuse” on page 47).Failed on remote control✔ Verify the optical side of of the IR-USB cable connected to multimeter —the Keysight logo should be facing up.✔ Verify the baud rate, data bit, stop bit, and parity settings in themultimeter’s Setup mode. (Default values are 9600, 8, 1, and none.)✔ Verify that the driver for the IR-USB interface is installed.