Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

Another owner sent in his audio head unit for refurbishment.

Initially, he wanted to send in the A/C CCU board for servicing as it could only operate when the fan speed control was set at max (typical CCU failure mode) and after reading my blog about the capacitor failures on other parts, decided to have his head unit serviced at the same time as he experienced no power, no display issue long time ago but it fixed itself with no reason.

So, quick check in radio mode and since it worked fine, started opening the unit.






As soon as I removed the base cover, I started feeling suspicious as I saw many finger prints as well as scratch markings on the bottom circuit board.




The soldering at the four GND fixing screws were also looked very strange.
It should be smooth if carried out by Alpine engineer and not like this.
Clearly, someone worked on the unit in the past.




Some sort of condensation or moisture entered the bottom side of the unit???




As seen on many head unit, the On/Off push button as well as the volume control ring were scratched and showing the shiny appearance due to frequent operations.
They were initially in matt finish.




As soon as I removed the cassette module, I found this.
Another head unit with burnt ACC line.

Normally, it will happen when the Bose speaker AMP was burnt or when someone connected the iPod adaptor at the CD changer port without checking the state of the head unit first.
I’ll never connect any aftermarket device to the CD changer port without first checking the ACC line and modifying it as many owners including myself experienced smoke coming out of the cassette door/window.


Funny thing was, despite the broken ACC line, the owner didn’t mention anything about not having power at the head unit.


And after removing the parts further, I understood why.





Someone soldered in 5A fuse covered with sticky clear tape with fly lead poorly soldered to the terminal......
Not only amazed by what was done for repairing but also no idea how the 5A rating came from......


So, obviously, removed it and also carried out general check up on several key areas on the board as I have no idea on how far the damages were done.






Started replacing the capacitors.




Double checked and confirmed that the scratch marking at the bottom board didn’t cut through the track.