Category Archives: Case study

Jul16
Youtube: QC 7 Tools – Fishbone (Cause & Effect Analysis) Diagram Introduction

Many of you might already know what a fishbone diagram is. But do you know how to actually draw one? And what should you watch out for when creating one? As the name suggests, the diagram looks like the skeleton … Continue reading

Jul10
Customer Complaint About Oil Contamination on PCB: Who’s the Real Culprit? (FTIR Analysis)

In the previous article, Workingbear mentioned a serious DOA (Dead on Arrival) customer complaint involving one of the company’s products. Most of the defective units had unresponsive keypads—specifically the 3, 6, and 9 buttons—and it was eventually traced back to … Continue reading

Jul03
[Case Study] Troubleshooting a Customer Complaint – Keypad Malfunction Caused by Oil & Powder Contamination on the PCB

This article shares a real case from Workingbear’s past experience dealing with an urgent customer complaint. One day, Workingbear was suddenly assigned to fly to a factory in China to “hunt for oil.” My manager even warned, “If you don’t … Continue reading

May29
Uncovering the Culprit: How CAF Turned Out to Be the Hidden Cause Behind PCB Micro-Shorts — From Suspicion and Analysis to Solutions

Workingbear’s company was having a tough time with a strange issue: intermittent micro-short circuits inside the layers of the PCB. Since the shorts didn’t show up near any components, it was really hard to figure out what was wrong. Recently, … Continue reading