Jump to content

Re-capped board, issues remain. Ideas?


Recommended Posts

I've got this SE/30 logic board that I re-capped today and it's still having some issues, would be curious if anyone has any troubleshooting tips for areas I should look at next.

 

1. No sound - no boot chime, etc. I haven't exhaustively tested this, however I suspect there's some sneaky issue on the logic board. The internal speaker is definitely connected, but I haven't swapped in my good board to verify the speaker is good. haven't tried the audio output jack yet... I'd be surprised if the speaker is bad, but I guess stranger things have happened. edit: maybe the old caps leaked under the sound chip and it needs to be removed, cleaned, and put back?

2. 1 out of every 8 vertical lines of pixels is dark. (see picture)

 

Both of these issues existed before the re-cap; I was really hoping I would get lucky and be done with the repairs at this point. After reading the repair guides I'm going to go looking for a short or a broken trace around the audio connector, and try different RAM chips to see if it effects the video in any way. I find it curious that the machine boots and recognizes all of the RAM but still shows the vertical line failure...

 

I've got three other SE/30 boards - one fully functioning logic board that I re-capped a few years back, one board that works except no sound, and one that has some serious corrosion problems, so if I need to use one as a donor or test with parts from the good one those are some possibilities!

 

Cheers!

 

1888504946_2020-12-1323_03_13.thumb.jpg.c60845da8f0f39138ef2894a99455df1.jpg

Edited by zcoffin
Link to post
Share on other sites

Fixed the bad video line(s), good call! Huge shout out to the maintainers of the re-built schematic files at https://github.com/mishimasensei/macse30mlb; they came in super helpful! I'm guessing that corrosion from the cap that I replaced had damaged the traces under that chip. I guess I won't get away with a short little solder bridge for this broken trace... Only one line was out when first powered on, but after a few minutes the adjacent line went out as well. Unfortunately (fortunately?) all these traces are top-side, so big ugly top-side bodge wires it is!

 

Now I'm on to the audio issue. A little more info: the headphone jack works great! And the internal speaker (through the connector wire) measures at 63.5 ohms; so I know that's not open or short... Maybe I'll look into the detection for "is a headphone plugged in" - maybe that's just stuck in the "yes" position. That sounds simple enough.

 

977254824_2020-12-1421_27_50.thumb.jpg.73b22c21f5addb6638898b92d66d4729.jpg

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...