Showing results for 
Search instead for 
Did you mean: 

How do I change the CMOS battery on my VXIpc model 870?

I have a VXI slot 0 pc model 870 with a dead CMOS battery.  I can't seem to find any documentation detailing the replacement process.  Where is the battery located, and what is the best way to get to it?
0 Kudos
Message 1 of 4

Hi Ateeple

I found the following procedure in one of our internal documents, we are currently working on getting it set up on an external page. Thanks for bringing this to our attention.

Scott M.


1. With the controller removed from the chassis and laying on it solder side cover, remove ten flush set Phillips screw.
2. With the screws removed lift and rotate the component side cover , starting from the end closest to the face plate, this will allow the cover to clear the connector on the power extender pwb.
3. Remove the access cover to the PCMCIA ports, under this you will find two more flush set Phillips screws that need to be removed.
4. If the controller is equipped with only a FLOPPY DRIVE, PCMCIA port and AT/PCI extender remove the two screws that secure the extender to the floppy drive support platform, remove the extender from the motherboard
5. There should be a short standoff and a Phillips screw holding the platform to standoffs underneath, remove.
6. Near the edge of the mother board, under the floppy drive, there is a ribbon cable that connects the floppy drive to the mother board. Find on the connector a small lip at each end, gentle lift both ends about 1/16 of an inch. This should free the ribbon cable from the connector.
7. Carefully lift the floppy platform and disconnect the ribbon cables that connect the mother board to the PCMCIA ports that are also attached to the floppy drive platform, there are no release latches on these connectors, gentle rock them free.
8. You should now see a small yellow box about 21mmL X 17mmW X 8 mmH, this should be the only box that is on top of another I.C. that is soldered to the mother board. In some cases the box may be black as it was provided by another vendor. There should be a reference designator on the mother board that indicated U31.
9. The CMOS battery has its own hold downs molded into its case. Gently rock the battery loose.
10. The replacement battery should have a polarity tab on the bottom; match this with the notch in the base I.C.
11. Reverse all the previous steps to reassemble the controller.

Applications Engineer
National Instruments
0 Kudos
Message 2 of 4
Thanks for the help!
0 Kudos
Message 3 of 4

Do you have the CMOS batteries in stock to order?

0 Kudos
Message 4 of 4