1708 controller not working on battery power, USB all good

[BuckT]

All fixed now and many thanks to RDC for posting the diagrams for the 1708 controller. Problem was traced to Q8 not turning on with ground applied to base. Q8 was open circuit and the trace from R27 to through hole had blown. Trace replaced with enamelled wire, Q8 replaced with suitable PNP bi-polar transistor and all working. Thought I'd post in case anyone has a similar problem. Photo shows repair before Q8 replaced.

https://ibb.co/rvxTMZx

[vojo]

Thanks

[john.jenin]

Hello, I'm having this exact problem too. Would you mind sharing the details on how you fix this? I know you already mention it but I don't really understand what is Q8 and R27.

[Ricardo Portes]

Beauty Friend! Do a test on some PCB components: D26 - Q9 - Q8 - R27 - R29, in my case the D26 was burnt, also check the track that goes from D26 to U4 as it is in this jamper in the photo, in my case it was also open .
Hope it helps you!