The postal Gods were kind to me and the "back-up" GC-0308 camera module arrived this morning
I thought Customs clearance would delay things, but not this time.
I have spent much of today working on the UTi-690B in a determined effort to repair it. I installed the new GC-0308 camera core, booted the UTi-690 and........ no change
The camera still halted at the 100% boot point. A check on the boot log showed no change from when the original GC-0308 was installed. I tested all of the replacement GC-0308 cameras on my ESP32-CAM module and all worked as expected. The original GC-0308 module is known to be faulty but I tested it again to make sure, and it is non responsive.
Whilst the UTi-690B complains about the lack of response from its GC-0308 camera core, I have now tried 3 different GC-0308 camera cores in it and none change the symptoms. As all are proven working, it would suggest that the problem is not the camera core. The original GC-0308 core did have a failed MLCC across is power rails that was drawing excess current, but the core was found to also be faulty after investigation. I have investigated possible causes of failure, such as a fault in its dedicated power supply IC and went so far as to stress test that IC to eliminate it from enquiries. It appears to be operating correctly with no transients or noise at its output to harm the GC-0308. The cause of the original GC-0308 failure is not known but it is possible that the MLCC failure has nothing to do with the camera failure and it is just coincidence.
With the GC-0308 camera module hardware eliminated from the investigation I have had to look at the data side of things. Could UNI-T have used a custom GC-0308 camera core in their product that the firmware needs to identify ? I very much doubt that as this is a building block component with no reason to make it unique in any way. All power and data lines associated with the core have been tested yet the GC-0308 is not working in the UTi-690B chassis.
I have done my best to identify any issues with the Linux firmware but found nothing unusual that could be causing this fault. I came to the conclusion that I am likely dealing with either some exotic firmware corruption or a failure in the SoC hardware. File substitution in the Firmware from a known good copy did not remove the fault so that leaves the SoC as a prime suspect and there is nothing I can do to repair that.
After spending a fair few hours on this camera I think it is time to declare this patient deceased. I shall advise the owner accordingly
Sady you cannot win them all and these budget cameras are virtually "disposable" technology now.
I learnt a lot about the UTi260B/Uti690B during this investigation and I may create a separate repair thread dedicated to the various stages of the investigation and findings. If you own one of these and it stops working, do check the GC-0308 camera module current draw, in case the MLCC has failed, but be warned that there may be a deeper failure that is uneconomic to repair by a tech.
Fraser