Keithley TEC SourceMeter 2510, Service Manual, Page: 75 / 120

4-18 Troubleshooting Models 2510 and 2510-AT
Digital I/O +5V supply fuse replacement
An internal fuse protects the +5V supply line on the ENABLE-DIG I/O connector from
over-current conditions. Replace this fuse as follows:
1. Turn off the power, and disconnect the line cord and all other test leads and cables from
the instrument.
2. Remove the case cover, as covered in Section 5.
3. Locate fuse F101 on the mother board. This fuse is located near the ENABLE-DIG I/O/
RS-232 connector assembly (J1007) at the back of the board. See the 2510-100 compo-
nent layout drawing at the end of Section 6 for location.
4. Carefully unsolder the blown fuse.
5. Replace the fuse with one with the following rating: 0.6A, Keithley part number
FU-103, then solder it in place.
6. After soldering, clean the mother board as covered in Section 5, “Handling and clean-
ing precautions.”
No comm link error
A “No Comm Link” error indicates that the front panel processor has stopped communicat-
ing with the main processor, which is located on the mother board. This error indicates that the
main processor ROM (U168) may require reseating in its socket. The ROM may be reseated as
follows:
1. Turn off the power, and disconnect the line cord and all other test leads and cables from
the instrument.
2. Remove the case cover as outlined in Section 5.
3. Locate the firmware ROM, U168, located on the digital board. This ROM is the only
IC installed in a socket. (Refer to the 2510-100 component layout drawing at the end of
Section 6 for exact location.)
4. Carefully push down on the ROM IC to make sure it is properly seated in its socket.
CAUTION Be careful not to push down excessively, or you might crack the mother
board.
5. Connect the line cord, and turn on the power. If the problem persists, additional trouble-
shooting will be required.
2510-902-01 (E - Mar 2010)(Service).book Page 18 Tuesday, March 16, 2010 1:04 PM