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Faulty CPU Board - Can it be Repaired

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Hi, I have a faulty intermec printer CPU board. I'm proba... - Aug 05, 2011 by bobbydur  

#64779

Faulty CPU Board - Can it be Repaired | 5 August, 2011

Hi, I have a faulty intermec printer CPU board.

I'm probably in the wrong place but if anyone can give me some help, I would really appreciate it.

I manage to connect an incorrect thermal printhead to the printer and I think it has damaged the CPU board as nothing works anymore, even the display does not come on. I have checked all other boards on a working printer, they are ok. So it is definately the CPU. Are there any diagnostics I can carry out? Can it be fixed? Do you require any further info off me? THanks, Bobby

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#64792

Faulty CPU Board - Can it be Repaired | 8 August, 2011

Hail yes, we know how to fix things!!! You just need to tell us what to fix.

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#64793

Faulty CPU Board - Can it be Repaired | 8 August, 2011

So would you know how to fix this faulty board? Were would you start?

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#64795

Faulty CPU Board - Can it be Repaired | 8 August, 2011

I'm pretty sure that what Davef is suggesting is that rapair is one thing people here could definitely provide expertise for, but troubleshooting and identifying the failure mode (what needs to be repaired) is another thing entirely.

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#64801

Faulty CPU Board - Can it be Repaired | 9 August, 2011

Start by checking for hot spots on the cpu board if possible. An IC may have blown or shorted internally. It's probably a driver chip for the print head. But that doesn't explain why the display doesn't work, but if it's overloading the power supply, that could be the problem. Start there, try the simple things first. I'll ask the obvious question, any warranty?

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#64802

Faulty CPU Board - Can it be Repaired | 10 August, 2011

Hey, we used to make those things! Outsourced... Sorry, I can't tell you how to fix anything unless it has wheels or stepper motors, though.

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#64804

Faulty CPU Board - Can it be Repaired | 10 August, 2011

Is there an on-board fuse on the pcb? Check all the obvious solutions first.

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#64816

Faulty CPU Board - Can it be Repaired | 11 August, 2011

No warranty, and I would have no idea on how to check any of the parts you mentioned, I am a complete novice trying to save myself a few £'s. If its too hard to explain, don't worry. I have almost given up on this. I know nothing about boards.

I cannot see any on board fuses, can you?

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#64817

Faulty CPU Board - Can it be Repaired | 12 August, 2011

The only thing I see that might be a fuse is the green vertical axial leaded component next to the third from the bottom white 4-pin header. It's labeled ?718 or 710. I don't know if this is a resistor or a pico fuse. You can try to ohm it out. Another possibility is an over-current circuit that might be tripping due to a damaged/shorted component.

You can use an IR thermometer, fairly inexpensive, or the top-side of your index/middle finger to check for hot spots. Careful you don't burn yourself. Check the power rails for the appropriate voltages. You will probably have a +/-12V, +5V, and maybe a +3.3V bus.

Given your level of experience, aside from checking the voltages on the power buses and hot spots (), buy a new board.

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#64818

Faulty CPU Board - Can it be Repaired | 12 August, 2011

I will check that, thanks. What are the power rails by the way. What am I checking? Sorry for being useless :)

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#64819

Faulty CPU Board - Can it be Repaired | 12 August, 2011

The rails are being sourced by the regulators. Rails, bus, you can use them interchangeably. As far as what voltage? I have no idea other than my assumptions listed above, but more than likely you will have +/-12V and 5V. Depending on the age of the board, you may have 3.3V also. If so, you may or may not have +5V. There may be print on the board that tells you what the power should be.

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#64820

Faulty CPU Board - Can it be Repaired | 12 August, 2011

I mean what do they look like on the board. Please describe what you want me to check. I don't know what rails and regulators are :)

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#64821

Faulty CPU Board - Can it be Repaired | 12 August, 2011

I would say you have absolutely no hope of repairing this board. I'm sorry, this is not a knock against you, you just lack the technical expertise to make a go of it. Save yourself some trouble and find a new board or a repair depot that can fix it for you. Have you called the mfg?

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#64822

Faulty CPU Board - Can it be Repaired | 12 August, 2011

I believe you've gotten some wise advice about finding a working board rather than attempting repair. If you decide to attempt the repair, checking or replacing the regulators is a reasonable starting point (primary power). The next thing I would do is replace the first IC that is encountered when the module is plugged in. The IC's between the white connectors are likely to be line drivers and are a good bet if the connection is made to these connectors.

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#64833

Faulty CPU Board - Can it be Repaired | 16 August, 2011

Ok, thanks to you all for your excellent advice. I'm ready to put this to bed now but just before I do, maybe there is 1 more thing I can try. Can you see RESET printed on the board above the buzzer and below the battery? There are 2 silver points in a white bordered box. Can I short these points? Will it reset the board? What do you think?

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#64834

Faulty CPU Board - Can it be Repaired | 16 August, 2011

I doubt that will do anything. You have had the board powered down and powered back up, right? This will have the same effect. But hay, what have you got to loose?

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lt

#64835

Faulty CPU Board - Can it be Repaired | 16 August, 2011

> Hi, I have a faulty intermec printer CPU > board. > > I'm probably in the wrong place but if > anyone can give me some help, I would really > appreciate it. > > I manage to connect an > incorrect thermal printhead to the printer and I > think it has damaged the CPU board as nothing > works anymore, even the display does not come on. > I have checked all other boards on a working > printer, they are ok. So it is definately the > CPU. Are there any diagnostics I can carry out? > Can it be fixed? Do you require any further > info off me? THanks, Bobby

This is one of those "check the easy stuff first" suggestions........

In the upper/left corner, near the "Made in Taiwan" marking, is a number "0443"....this likely means that the pcb was made in the 43rd week of 2004....the assembly was likely made in late 2004 or early 2005. It is likely that the round dohickey in J30 (upper/left corner) is a coin cell (i.e. battery). If that battery has been in the board since 2004, it is could be dead. If you can operate a voltmeter, remove the battery and check its voltage....its intended voltage should be stamped on the battery's shell. If it measures low, or if a voltmeter is not available, simply replace the battery and see if the board comes back to life.

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#64839

Faulty CPU Board - Can it be Repaired | 17 August, 2011

It's unlikely that this is the root cause. The battery may be dead, but the entire board is dead. This battery is most likely used for data retention for volatile memory as a battery backup.

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#64845

Faulty CPU Board - Can it be Repaired | 17 August, 2011

Yes I have powered the board up and down many times and yes I have tried a different battery. This board should be able to work with no battery. I think I will have to pay for it to be fixed or find a replacement Many thanks

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