The cluster from a previous post came in a box with an additional, non-working CCU. It had been worked-on previously and some unknown clear coat was applied, covering a lot of capacitor liquid damage:
After removal of all capacitors the PCB was given a good scrub of the affected areas, down to bare copper, discovering multiple broken traces:
For the first time so far, the back side needed work, too
Nine bridges/repair wires had to be installed overall.
The first test run in the vehicle showed all functions and buttons to be operational but no display.
Replacement of the display with a known working one showed no improvement so the issue had to be with the CCU board.
After looking a bit harder, one remaining broken trace near C44 (documented in the blog) was the culprit.
After removal of all capacitors the PCB was given a good scrub of the affected areas, down to bare copper, discovering multiple broken traces:
For the first time so far, the back side needed work, too
Nine bridges/repair wires had to be installed overall.
The first test run in the vehicle showed all functions and buttons to be operational but no display.
Replacement of the display with a known working one showed no improvement so the issue had to be with the CCU board.
After looking a bit harder, one remaining broken trace near C44 (documented in the blog) was the culprit.
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