Although troubleshooting a CRT-based arcade monitor can be challenging, there is an effective solution that can make the process much easier: a troubleshooting flowchart! By utilizing the Wells-Gardner K4900 flowchart, you can troubleshoot your monitor with ease and avoid unnecessary frustration.
Typically, troubleshooting electronic boards and circuits in arcade games requires a significant level of electronics expertise. However, the K4900 flowchart simplifies the process by presenting a systematic approach that outlines the fundamental steps for identifying the most common components that could fail. Therefore, even if you don’t have advanced electronics training, you can still use the K4900 flowchart to effectively troubleshoot your arcade game’s electronic circuits.
How to use the K4900 Flowchart
Simply start at the START HERE section of the flowchart and follow each step until you have identified the problem with your G07 monitor.
Once you’ve reached the symptom for your issue the flowchart will recommend a component to replace (or adjust). In some cases you may be able to swap components to see if a problem moves. For example, if your monitor is missing red, you can swap the red and green transistors (i.e. Q204 and Q207). If the green goes out, but red is restored you can be sure that you have a failed transistor before ordering unnecessary parts.
If your monitor has multiple issues, you may have to return to the START HERE and re-follow the chart to find the next issue and its potential solution.
Wells-Gardner K4900 Flowchart PDF
If you’d like to download and print your own copy of the K4900 flowchart you can get the high-res PDF version by clicking here: K4900 Flowchart PDF
You may also want to download the Wells-Gardner K4900 Service Manual. (This version of the PDF had been OCRed and is text searchable.)
Warning and Risk of Shock
When using the K4900 flowchart, you must be aware that you are troubleshooting electronic components with voltages from 5V all the way up to 60,000 volts. The risk for electric shock is high. Troubleshooting should be performed with the monitor off, unplugged, and the CRT discharged. You assume all risks!