How to avoid 1802 01C9 error on IBM ThinkPad T30 T31

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How to avoid 1802 01C9 error on ThinkPad T30 T31

Reflash BIOS has risk! Some friends maybe say there is no T31! T31 is student type, quite few in market. most are T30.

If you use Intel, Broadcom bg/abg card on T30,there will be

1802: Unauthorized network card is plugged in
Power off and remove the miniPCI network card.

if you use Atheros bg/abg card, it will display 01C9 error after 1802 error.

01C9: More than one Ethernet devices are found. Remove one of them. Press <Esc> to continue

Which must makes you scratch your head and may call IBM/lenovo, but get nothing useful information.

What is the reason: because T30 BIOS doesnot recognise non-IBM wifi card.

Support Broadcom 4306 bg card, 4309 abg card.

Intel 2100 b card, 2200bg bg card, 2915 abg card.

Atheros 5212 bg/abg card, 5213 bg/abg card(some new 5213 and IBM 5212 5213 cannot work).

Please following this way

Please burn the iso file as image (how to burn h ttp://
download h ttp://
In windows install driver Ekahau driver
h ttp://

1. Close machine and insert wireless card. Then press Power button
2. Press ESC key
3. Enter sytem now ……(the first bootable device must be DVD-device/CD-Device)
4. In WARNNING press <OK>
5. CMOS 1802 whitelist Patch <YES>
6. Patch 01C9 error, <Yes>
7. Put out the CD
8. Restart

All ok now.

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