4020 SX (250-4902/3)              Battery               Faxback Doc. # 1605

┌───────────────────────────────────────────────────────────────────────┐
│For battery replacement, order:                                        │
│                                                                       │
│  Part Number   Voltage     Description                                │
│                                                                       │
│  CS 0232       3.6 volt    Lithium Clock Battery (3 pin connector)    │
└───────────────────────────────────────────────────────────────────────┘

The 4020 SX uses a long life lithium battery.  It powers the real-time
clock and CMOS RAM when the computer is turned off.  The clock maintains
the system date and time.  CMOS RAM stores information about your system
configuration.

REPLACING THE BATTERY

Each time you turn on the computer, it accesses a battery-backed memory
chip (CMOS RAM) that contains information about important devices in the
system as well as the time and date information.

The CMOS RAM battery should last at least three years of normal use.
When it fails, the following prompt is displayed when you turn on your
computer:

     Invalid configuration information - please run Setup program

Your computer uses a special lithium battery.  Contact your Radio Shack
Service Center to select an appropriate replacement battery.  If you wish,
a technician at the Radio Shack Service Center will install the battery
for you.

WARNING:  Improper handling of this special lithium battery can be
hazardous.  Never recharge the battery, disassemble it, or heat it above
100° C (212° F).  Never solder directly to the battery or expose the
contents of the battery to water.

Follow these steps if you choose to replace the battery yourself:

1.  Run the Prepare System for Moving utility if any hard disk drives
    are mounted in the computer.  Remove the computer cover.

2.  The battery is located under the expansion adapter cover near the
    speaker at the front of the computer.  Remove the battery from the
    Velcro fastener.

3.  Disconnect the battery from the connector marked J3 on the main logic
    board.

4.  Attach the new battery to the velcro strip.

5.  Connect the new battery to J3.

6.  Run the Setup utility to enter and store the configuration
    information.

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