Good article.
My favorite feature of an old school incandescent test light is that it requires current to illuminate and is therefore a better indicator of a good circuit than a voltmeter or an LED test light. You can get a 12 volt reading on a voltmeter or light an LED through a pretty crappy connection but to light a test light you need a good one. More than once I’ve quickly found a connection problem in a lighting circuit using a test light that someone had spent hours trying to track down with a meter.
A test light is also the quickest way to test fuses in a fuse box. Turn on the key and the headlights and the light should illuminate when you touch the probe to each end of the fuse. No need to pull the fuses and look at them and because it’s so quick to check them it’s not even worth figuring out which fuse might cause the problem you’re troubleshooting. Just check them all and if you find a bad one then confirm it’s in a related circuit.
Next article: how to repair your burned out sensitive electronics from using our test light and poking the wrong bits 
Paul_VR6 (Forum Supporter) said:
Next article: how to repair your burned out sensitive electronics from using our test light and poking the wrong bits
Exactly, I…
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