Technical data

Field Replaceable Units
Removing and Replacing the Real-Time Clock Battery
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Removing and Replacing the Real-Time Clock Battery
This section provides step-by-step instructions for removing and replacing the real-time
clock in your Model 743.
Preliminary Requirements
WARNING: Lithium batteries may explode if mistreated. Replace
battery with only a Matsushita Electric BR-1616
three-volt lithium battery (HP part number 1420-
0525). Use of any other battery may cause fire or
explosion. Use the following guidelines when handling
old batteries:
Do not put lithium batteries in fires.
Do not try to recharge lithium batteries.
Do not disassemble lithium batteries.
Removal
Perform the following steps before removing the RTC battery from your Model 743:
1 Remove the 743 from it’s chassis.
2 Remove any RAM or accessory cards installed at the board computer’s left position.
Replacement
Follow these steps to replace the RTC battery:
1 Locate the battery behind the left RAM connector. It is held in place by a spring arm
marked with a “+”.
2 Push the edge of the battery, slipping it out of place, and remove the battery.
3 Install the new battery with its `+’ side up by slipping it under the spring arm - AVOID
LIFTING THE SPRING ARM.