Nikon Coolscan 4000 intermittent LED self test failure

[hwy17]

I've acquired a Coolscan 4000 in questionable condition.

It successfully starts about half the time and I can see the LED RGB self test running. And the other half of the time it makes the same sounds but I don't see the RGB's running and then it errors after the second movement sound.

Just wondering if anyone has any insight about whether this likely indicates imminent total failure of the light source, or can be explained by an adjustment problem like alignment or connection re-seating.

I have not got it set up with a computer for a test scan yet but will in the next day or two and will report the result of that.

It was represented as in used but working condition, and also represented as intact but arrived with a totally destroyed faceplate. So I have the option to get a full refund but it was cheaper than the going rate for a good condition model so I am still interested to see if it can be salvaged into functional operation.

 

[FotoD]

My guess is that it took a fall during transport that broke the front and an internal plastic part.

I think my CS 4000 had the same symptoms when I got it. I couldn't get a refund so i "fixed it". It's not like new, but it does scan.

 

[koraks]

So I have the option to get a full refund

Frankly, that sounds like the way to go. This unit evidently suffered major damage. You might be able to fix an intermittent light source problem, but what's next? The moment you start fixing things on the device, it basically implies you've accepted the unit and you can't go back to the refund.

 

[FotoD]

I agree that a refund is the reasonable way to go.

Having said that, these scanners can be hard to find at a fair price, so I understand if you hesitate to let it go.

I now remember this page, it has good instructions for disassembly:

Nikon Coolscan 4000 disassembly and scan head gear repair

This image shows where a small plastic past can break if you drop the scanner. It's 24 steps to replace it. But you don't have go many steps before you can see the part and check if that's your problem.

 

[hwy17]

Yeah I'm fine navigating my options to proceed as far as the purchase, just wondered if anyone had encountered the specific symptom of intermittent light source self test failure.

 

[FotoD]

I don't remember the order of the steps in the calibration, but it will abort when it comes to a step that fails. Have you established that it is the LED test that fails and not a test before that?

 

[hwy17]

I don't remember the order of the steps in the calibration, but it will abort when it comes to a step that fails. Have you established that it is the LED test that fails and not a test before that?

I could still study it more carefully but it does seem to me like it completes the home point detection successfully and then only errors out at the LED testing step.

Nikon Super Coolscan LS-4000 ED and LS-5000 ED: diagnostics and troubleshooting.

 

[FotoD]

Ok, that was a good webpage. My scanner failed on step 3. It wasn't the optical interruptor. It was a mechanical problem that prevented the carriage to trigger the interruptor. And it was possible to fix.

If your scanner has problems on step 4 then it could be more serious. Hard to know.

 

[hwy17]

Ok, that was a good webpage. My scanner failed on step 3. It wasn't the optical interruptor. It was a mechanical problem that prevented the carriage to trigger the interruptor. And it was possible to fix.

If your scanner has problems on step 4 then it could be more serious. Hard to know.

View attachment 401471

That's interesting about that source naming failure at this step as either LED failure or motherboard VRM. Because it seems less likely to me that an LED would failure intermittently, but a VRM certainly would. I hope they're surface mounted rather than pad mounted.

 

[hwy17]

To satisfy people's curiosity though, the way I'm considering proceeding is with a partial refund to accept it.

I know a lot of people would rather just spend more on one good item, but I'd enjoy more to have several questionable examples if I can frankenstein them into a working one and be left with a parts library.

 

[koraks]

Sounds like a good compromise.

Verifying the different power supply voltages sounds like a good idea. I do wonder if some are activated only as needed; this can be confusing if you're measuring voltages and they magically disappear and/or re-appear, which does not necessarily indicate failure.

But really, I'd start by very carefully checking for any apparent mechanical damage. The unit has dropped hard, evidently, so the most probable cause of this init failure IMO is some kind of mechanical damage resulting from the same fall.