***SUPPORT FOR IBM T21 with ERROR 0175: BAD CRC1, STOP POST

Message

KW2500 · #1 Post by **KW2500** » Fri Nov 10, 2006 6:07 pm

Hello Forum--

I am trying to repair my IBM T21 (model 2647-6BU). When I turn the machine on it freezes after the IBM Thinkpad Logo screen and shows ERROR 0175: BAD CRC1, STOP POST TASK.

I've done quite a bit of research on this error online and on the forum here. After initially calling IBM support, they recommended that I buy and replace the CMOS battery. I replaced the battery yesterday, but I'm still experiencing the same error and the machine is still failing to boot properly.

I now suspect that there is a malfunction with the system board. I researched and found another site last night (www.allservice.ro) that offers software to fix this CRC1 Error, but this requires soldering the eeprom chip underneath the RAM cards, providing a dump and rewriting the eeprom. With my lack of computer hardware experience, I'm afraid that if I do this, I could permanently damage the machine. I located one person, who was very highly recommended, that can repair the CRC error for $100 or replace the system board for $200, but this is without any guarantees that the CRC error will or will not return.

Does anyone have any new advice on fixing this BAD CRC1 error for the T series? Is the cost of this repair worth it....?

If not, I am considering buying another T21 and inserting my old hard drive into the machine for recovery. Will my hardrive (Hitachi Travelstar 20GB) be compatible with any T21 model? I can't currently afford a newer model, so I would use this other T21 as a band-aid until I can afford a T60 or T43.

Do you think buying a second T21 is worth it? Or are these T-series machines fatally flawed? (Mine worked very well for four years, but I'm wondering if this is their life expectancy.)

Please let me know if anyone has any viable advice and thank you in advance!

Kevin
ktt2500@yahoo.com
Santa Monica, California, USA

#2 Post by **rkawakami** » Fri Nov 10, 2006 6:57 pm

Welcome to the forums at thinkpads.com!

KW2500 wrote:I am trying to repair my IBM T21 (model 2647-6BU). When I turn the machine on it freezes after the IBM Thinkpad Logo screen and shows ERROR 0175: BAD CRC1, STOP POST TASK.

That error refers to a Cyclic Redundancy Check, a checksum or data error flag if you will. My understanding on these types of errors is that you can:

1) Re-program the original EEPROM with good, known data
2) Remove the EEPROM and replace it with another pre-programmed one
3) Replace the entire motherboard

Option #1 is what you found on that site. That has a good chance of working if properly done. The system information contained within the EEPROM would be maintained (i.e. system serial number and other stuff). Option #2 is normally offered by eBay sellers but requires that you do all of the "dirty" work (unsoldering and soldering). However, that means your system serial number gets wiped out. Option #3 is usually the route that most people take. It requires the least amount of electronics/computer experience. There is a maintenance manual from IBM which details the steps required to remove and replace the motherboard. Sources for the new motherboard are IBM ($$$$, if even available) or eBay ($$, you just need to find a trusty seller) or here in the Marketplace ($, if somebody has one for sale).

The possibility of another board getting the same CRC error is slim (in my opinion). If you are not trying to do anything funny with the BIOS and maintain the CMOS battery properly, the system should operate correctly for years.

The cost of the repair depends entirely upon what you think the system is worth. You could probably pick up a slightly faster T22 or T23 for just over $200. Your plan to buy another T21 is safe since you will be able to use your existing hard drive. If you try to put the T21 drive inside a T22, I'm not sure but it might work. If you tried putting it into a T23, I am almost positive that it won't work (at least not without Windows totally reconfiguring itself). The hardware differences between a T21 and T23 is significant.

As far as the T-series hardware reliability is concerned, they have their "bugs" like any other system. There are known issues with the T2x systems which don't seem to occur with the T30 and vice versa.

Orevin · #3 Post by **Orevin** » Fri Nov 10, 2006 6:58 pm

Hi Kevin,

Welcome to the Forum!

You can replace the system board they are about $50 on eBay, even less if you are patient. Any board from a T20, T21 or T22 will work.
Just did a quick search and found this offer on eBay.

However, if you want to get another T21, your old HD will fit.

KW2500 · #4 Post by **KW2500** » Fri Nov 10, 2006 7:13 pm

Thank you Ray and Orevin for your detailed and expeditious responses! I will look into a system board replacement and continue to search for back-up T21s and T22s.

If anyone on the forum is selling a compatible T21 system board for a decent price, please let me know. I can pay via Paypal or money order asap.

Thanks very much.

Kevin
ktt2500@yahoo.com
Santa Monica, California, USA

basscleff · #5 Post by **basscleff** » Sat Nov 11, 2006 4:54 pm

I can help you repair the board, but it will take some time.
pm me for details.

#6 Post by **Kyocera** » Sat Nov 11, 2006 5:27 pm

Moved this here from the marketplace.

whiteivory · #7 Post by **whiteivory** » Thu Nov 16, 2006 4:23 pm

1. I'm a newbie in this forum, so I apologize if this is the wrong one to write in.
2. Possible reason for CRC1 (stop post): I remember reading on another forum of one possible reason that this error occurs. During boot-up, if the BIOS is written to and a power loss of both battery AND AC power occurs, it can corrupt the chip. Normally, BIOS is not written to and is protected during bootup, but then again, I didn't design the mobo circuits nor the firmware. Of course, this shouldn't happen...but I suspect that is why IBM/Lenova (and others) caution you to have both a charged battery AND AC power available and constant during a write process.

I'm an avionics tech by trade and even with EAROM's and non-volatile memory (NVM) locks, we've seen this occur in some of our avionics equipment...such as a power-up/power-down cycle being commanded before the power-up cycle completes. Really messes the EAROMs up on our older legacy units. Fortunately, we can run a blanking process and erase them...but not so the TXX Bios chip.

I purchased a mobo on eBay...thought unplugging the BIOS battery would fix it (reset it)...and was sadly disappointed. Mobo was too much hassle for me to work on (I couldn't even figure out where the BIOS chip was...it wasn't in a socket), so I junked it.

If any of the above is incorrect, please let me know...gently! Good luck!

Treat me as I treat you...fairly with respect and dignity...and we'll all be happy!

basscleff · #8 Post by **basscleff** » Fri Nov 17, 2006 11:14 am

in my experience, the eeprom at that point is damaged, and cannot be reset. It needs to be reloaded to the chip
- by a eeprom dump
- repair of the eeprom bin file (if not able to be repaired, then you need a similar eeprom bin file)
- re-uploaded to the eeprom chip.

I know a few sources to have this done, but unfortunately, I havwe not found a "free" solution...still looking