Thinkpad R40 Ethernet doesn't work, Wireless does

We have an IBM Thinkpad, R40, model 2681-4GU.

I am a 20+ year programmer, system builder & tech specializing in system forensics and system security compromising.

This laptop computer has me stumped.

This laptop lost it's ability to use wired / motherboard Ethernet based networking. The computer will show "A network cable is unplugged" on rj-45 connections. When the on board rj-45 port quit working the following steps were taken:
1. Device Manager showed Intel Pro/100 VE working properly.
2. Several different patch cables were used to verify cables not the cause.
3. HiJackThis showed nothing unusual, no hidden toolbars or background processes running.
4. A series of complete virus, spyware / malware scans were performed, nothing found.
5. A newer BIOS version was found so BIOS was updated to latest version from IBM.
6. Newer drivers were available so the drivers were checked and updated from IBM and Microsoft.
7. A 3Com PCMCIA 10/100 card was installed and Device Manger showed it was working properly but the systray showed "A network cable is unplugged" on the rj-45 connection.
8. A wireless USB device was installed and it connects properly.
9. The computer has be wiped clean and a new XP Pro image was installed and tested with same results.
10. Updates applied to the system with the same results.
11. PCMCIA slots are functioning properly with other plugged in devices.
12. Installed a Linksys USB10T rj-45 in a USB port and it can now attach to a wired network.
13. The IRQ 11 is shared by several devices with different addresses for each

Have you heard of this happening? How can a system block motherboard based rj-45 ports but not wireless or USB? Any thoughts on how to restore the motherboard based port to active status so the rj-45 can be used?

Given this is a laptop with the built in LAN, do you know of a testing method for the port and also, why would a working / tested PCMCIA LAN card not work when installed? Is there logic in the BIOS not accepting motherboard attached / based LAN ports?

Testor,

I have the same ThinkPad R40 – 2681-L7U, and am having the exact same problem with the Ethernet Port. This computer was used by my mom and it got very little use. I am unsure when if ever the Ethernet cable was used because when I aquired it last week, it was running off a Netgear 401 wireless PICMA card. Ok enough about its history, here is what I have learned after wasting a tremendous amount of time with this problem.

1. Reinstalled from the computer’s backup parititon - XP pro (no service pack)
2. Installed from the Netgear Website, the driver for the Netgear Wireless 401 PICMA Card. (Because the Ethernet port wasn’t working) I downloaded this on another machine and transferred via USB drive.
3. Using the Netgear card, did all XP updates first – SP1, SP2, and all the other upgrades except for Explorer 7.
4. Installed Microsoft .NET 2.0 and then upgraded it to SP1 (or whatever it was named). After all updates to XP SP2, Micorsoft ask for no more updates!
5. Next, updated the Lenovo ThinkVantage System Update to latest off their website. Using that software, installed all the new drivers form the Lenovo website. When I was complete here is what was left from the ThinkVantage Software window:
a. 0 critical ones left
b. 0 Recommended ones left
c. 5 Optional ones left.
i. Active X
ii. Adobe Flash
iii. ThinkPad Embedded Controller Program Update (ThinkAdvantage has installed this and I think I have updated the H8 bios – 1.27 It hink - but it is still listed here. Am I doing something wrong?)
iv. IBM Thinkpad Audio Features (ThinkAdvantage won’t install this)
v. RecordNow by Sonic (ThinkAdvantage won’t install this)
6. I uninstalled the Netgear Wireless card 401 software.

Ok why tell all of this? Because I have added absolutely nothing else, and I too can not get the Ethernet Cable to be recognized. I have used 3 different patch cables, all work in another PC connected to my Linksys Router WRT54, but do not work on the IBM Thinkpad R40. However, I have discovered one thing.


I uninstalled the Windows XP Ethernet driver using the device manager, and I downloaded from another machine from the Intel website - Intel PRO/100 VE Desktop Network Adapter driver (PRO2KXP). Used the easy install wizard. Now with this software installed, using the device manager for the Ethernet port, there are a few new tabs. Of primary usefulness is the LINK SPEED tab. Using it, I was able to get the computer to at least flash the Ethernet ports green and yellow LEDs. NOTE here is the process because it didn’t work simply after the install:
1. Remove old driver
2. Install driver
3. REBOOT
4. Link Speed>>>>Diagnostics button>>Hardware Tab>>Run Test (This is the first sign anything works)
5. REBOOT
6. Link Speed>>Identify Adapter button>>Start (now the green light flashes) (NOTE This 2nd test will not work if you didn’t do the Hardware test first.)

So what is the final result from this? Really nothing because the damn Ethernet Port still does not work. The motherboard seems to see the port and it seems to be availalbe. Although with the XP driver, I got no LED lights to light up ever; However you can ping the port and you get a good response – at least that is what the Lenovo site said – sorry, oh yeah I forgot, I pinged it while I had the XP driver installed at 127.0.0.0) The ping also works with the Intel Driver. So it looks like perhaps it’s a bad pin? None look bad staring in with a flashlight. Sometimes these ports are finiky with the Ethernet cable but usually enough pushing and prodding causes at lease the green LED to come on once…After 8 hours of testing (I told you I have been wasting a tremendous amount of time) I did not see that once.

One last note, I did make the computer use the modem to dial out. I think I read while working on this problem that the modem and Ethernet port were part of the same hardware, so I just wanted to make sure it was working. I don’t have anywhere to dial to so can not test the TCP/IP portion of all of this, however, the Thinkpad did dial out successfully to my voicemail (I heard my message through the speaker)


Well if anybody comes up with a cure let me know. Probably should have just bought an USB to Ethernet adapter for $20 bucks and saved myself the time wasted and headache.

Doug
dw1046@mac.com

I've had this problem on two thinkpad X61s models. The first laptop went back to Lenovo and they replaced it, then second laptop I've just fixed with a two minute call to their support line!

Go into BIOS Setup (F1 key on boot up), go into 'config' and then 'network' and press F9 to reset the BIOS to its original settings. Then F10 to save and reboot and... presto... the Ethernet info worked again.
Apparently, the BIOS gets corrupted according to the Lenovo support guy.