Tom’s £2,000 Amprobe cable-tracing kit, purchased for work, stopped working after its signal generator sat unused for years. Fluke’s service department asked for at least £600 to attempt a repair, following an inspection for which £70 had previously been charged. Tom sent the device to the [Buy it Fix it] channel on YouTube.
The inspection ruled out power and display problems; logs obtained through the serial port showed that the boot image in the 128 MB NAND Flash could not be verified because of corruption. When the Flash chip was removed and read, the data appeared intact at first glance, but after an unproductive process with the Gemini chatbot, the working firmware in the device’s other unit—and especially the bootloader—was compared. Several bit changes were found in the bootloader section, potentially caused by charge loss in the Flash cells. Once the corrected image was written, the device booted again with firmware based on Linux 2.6. Replacing the NAND chip was recommended as a permanent solution.
Why it matters
This case shows that failures in high-priced technical equipment do not always stem from power, display or visible hardware problems. Sitting unused for years can affect the boot software because of charge loss in NAND Flash cells, creating the impression that the entire device has failed while the problem is actually confined to a specific memory section. Comparing the firmware and bootloader in the other working unit highlights the value of technical data that can be accessed before turning to the manufacturer’s service department for a diagnosis. However, although correcting the software image got the device working again, the fact that the memory chip still needs to be replaced for a permanent solution underscores the difference between repair and long-term reliability.