Team-BHP - DIY: Cost effective car fuse tester

When my car voltage tester failed early in the morning (right as I was trying to hardwire a dash cam), I needed a quick and cost-effective solution without waiting for the market to open or an online delivery. So, I came up with this simple DIY fuse tester, which worked perfectly.

I used an unbranded car interior LED light I already had, extended its wires, and made a few tweaks. The negative wire was looped through a hole in a cloth clip, and the positive wire was attached to a safety pin.

In just 10 minutes, and at a total cost of Rs 50, I had a functional fuse tester.

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Please if you can elaborate how you used this to test fuse.
I used this coin type led recently to replace the festoon bulb in my Zen’s cabin light. It’s much brighter than the original festoon bulb which also goes dim after a few days. Costs super cheap at Rs. 10 each. I even put one additional lamp in the boot and wired it through a door switch activated by the tail gate.

Quote:

Originally Posted by saket77 (Post 5908567)

Please if you can elaborate how you used this to test fuse.

My objective was to identify a fuse that continues to draw power even when the vehicle is turned off (To hardwire the dash cam). With the key in the off position, attach the cloth clip to an unpainted metal surface of the vehicle to establish a ground connection. Then, touch the pointed end of the safety pin to the exposed metal contact of the fuse. If the fuse is receiving power, the LED will illuminate.

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To test for a blown fuse with the vehicle turned on, the LED should light up when the safety pin touches both sides of the fuse. If the LED does not glow on one side, the fuse is blown.

Quote:

Originally Posted by bravo82in (Post 5908621)

My objective was to identify a fuse that continues to draw power even when the vehicle is turned off (To hardwire the dash cam)..

These day many cars take anywhere from 15-60 minutes to fully power down. E.g. My Jagaur still draws about 4-5 amps when you turn the ignition off. It takes quite a while for it to turn all the systems off. Also, as soon as you open a door, or the hood and so on, it powers back on again.

The principle is explained in this thread about trouble shooting parasite drains.

https://www.team-bhp.com/forum/techn...te-drains.html

Jeroen