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MP39

macrumors member
Original poster
Aug 6, 2016
54
29
Did initial troubleshooting, but looking for some help:

Setup:

Mac Plus, 4MB (received from eBay, everything appears to be working fine with no issue).
Floppy EMU HD20
ImageWriter II/L (Model G0010 (C0090LL/A), the final revision released with 24KB RAM built-in, received from eBay, condition was described as "Powers On" but nothing else)
Direct Serial Connection using Mini DIN-8 cable (purchased new 10ft serial Mini DIN-8 M-to-M from Amazon).

Issue:

ImageWriter won't print anything from Mac Plus.

Troubleshooting:
Tried printing with System 6.0.8 and System 7.0
Made sure Imagewriter was selected in Chooser and was correct version
Reinstalled Printing Disk
Verified correct port is selected and that cable (new) is seated into both Mac Plus and IW2 port.
Also, tried moving over to modem port and selecting just to check in case one port was possibly bad. No change.
Multiple Reboots and Power On/Power Off of printer.


Observations:
IW2 successfully powers on with carriage moving to left and returning to the middle.
No error light.
Select is depressed and lit.
DIP switches checked and set at defaults per IW2 manual.
Verified no add-in card or AppleTalk Card (physically inspected as well as Self-Test confirms No).
Printer Self-Test successfully runs and prints fine.
When I printed from system 6.0.8, the Print Dialogue came up like normal and appeared to be up the whole time it was "sending data" for the print job and then disappeared when complete. The whole time the IW2 is just sitting there not doing anything -- yes, the Select light was on to receive info. Nothing! Same behavior under System 7. Print job sends and it pauses, completes, and nothing happens with printer. I never get an alert saying something is wrong with printer or that it could not communicate with printer. Seems like the Mac Plus is thinking it is sending everything over just fine?
B&W vs. Color Ribbon doesn't make a difference. Both do Self-Test fine.
Cosmetic observation - I did take note that the left LED on the Print Quality IW2 Panel is out, but the button still functions as intended, and the selections change with each push as expected, so I don't think this is related at all.

Thoughts:
Is the cable bad? (Don't have another cable to check)
Are the ports on the Mac Plus bad? (it would have to be both of them and I don't have another serial printer to check)
Is the serial port on the ImageWriter II/L bad?
Is this related to another board on the IW2 that's no good? Is is the communications board that received info from Mac to deliver to the Main PCB in IW2? I referenced the K Base IW2 Service Manual Online here: https://archive.org/details/manualzz-id-1199545/mode/2up
I also physically removed top of IW2 to make sure there was no noticeable PCB cap issues or other obstructions. I also verified to ensure ribbon cables were not pinched and that operation panel ribbon cable was clean and firmly seated in connections.

Any thoughts on my approach for troubleshooting this issue or for someone who is more technical and has already experienced this and knows what will fix I would welcome your suggestions! I'm excited to get to printing with this setup again and want to get to the source of the issue.
 
Last edited:

MP39

macrumors member
Original poster
Aug 6, 2016
54
29
For anyone else in a similar situation, I ended up finding this really good troubleshooting service manual for the ImageWriter II. In short, I ended up running the Loopback Test outlined. That ended up with result “Loopback Test Failed”. I suppose this means I could go through a series of resistor, capacitor and other circuit tests in main board outlined to target the culprit, but for me it will probably be easier to simply replace the main logic board. That is the route I am going to take. I wanted to share progress forward on my experience thus far. https://archive.org/details/Sams_Technical_Imagewriter_II
 
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watakoola

macrumors 6502
Aug 23, 2010
271
232
Australia
I have no solutions, just a comment:
It made me smile warmly to hear of someone using a Mac Plus and an ImageWriter. They were good times.
 
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