They arrived yesterday.
I always do a visual check under the microscope for obvious problems.
First the power regulation & microchips. Then I check the display interconnect, SMT resistors, and harness plug connections to the PC boards for cracked solder joints.
I opened all three of them up last night to take a quick look and take some pictures with my microscope camera that arrived yesterday as well. It works very well. Now I can take pics to show what I've found when looking at boards.
The components in the pictures look big but I can't read most of the markings without my microscope.
I won't have time to sit down and work on them til Saturday or Sunday.
The Compass/Temp mirror has a cratered TO252 78M05 SMT 5v linear voltage regulator. Usually this comes from reverse polarity on the power input or shorts on the output legs.
You can see the hole where the magic smoke escaped from the damaged 78M05 regulator.
I'll have to investigate to see what blew it up before replacing it.
This is an undamaged 78M05 on one of the other mirror boards.
The two Onstar temp compass mirrors have cracked solder joints on resistors and most of the display board interconnect header joints as well as several cracked joints on the connector for the cab harness... Business as usual.
