A few weeks ago I posted a blog post called “A Quick Fault Finding Tip…” and that generated quite a few emails regarding electrical testing and how to trace faults. In fact a lot of the other electrical posts I’ve done over the years still generate emails and comments (it’s always worth checkingback on some of th eolder posts to read the comments) I’m going to try to explain a technique that’s really handy to have in your tool box for general fault-finding.
Earth Side Testing
Most people who perform general maintenance on their vehicle, motor home or caravan will be familiar with checking the voltage of the vehicle or leisure battery using a multimeter. Great little things to have and personally I think everyone should be able to do the basics with one. So as a bit of a refresher I’ll go through this scenario with you. Checking the lights on your tow vehicle you notice one of the brake lights is a lot dimmer than the other. Let’s find out why. I’m going to simplify the circuit a bit it should give you the idea behind the principle.
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