Power Probe 3
The Power Probe 3 is a very powerful, compact, and useful diagnostic tool. I would recommended that any technician specializing in electrical diagnosis pick one of these test probes up. The Power Probe III is so easy to use; It could be used by a oil change guy, a general service tech, a master diagnostic tech, and even the back yard mechanic! This tool is easily one of the most useful in my toolbox. You wont regret getting one, I sure don't!
However, I do advise extreme caution with usage. Always remember to comprehend all wiring diagrams associated with the circuit you are testing. If directly connected to a computer component (such as ECM, PCM, EBCM, ect...) it is possible to permanently damage that module when applying power. Seen it before so please head my warning. Many sensors operate on 5 volts; supplying 12 volts to the circuit may fry the sensitive logic processor.
The Power Probe 3 is also able to supply 10 amps of current on a 12 volt circuit before the thermal breaker inside the tool trips. Many people will warn you about the dangers of this tool as I have, but to a knowledgeable technician, it is a very powerful and handy tool.
"With the press of a switch you'll have an instant hot lead or ground lead. Use the probe tip and ground lead simultaneously to power up components right in your hand. Instantly check components for continuity as well as identify positive, negative and open circuits without re-polarizing hook-up clips. Look for shorts without wasting fuses. The 20ft lead will allow you to test bumper to bumper without jumper leads. Audio tone indicates positive with a high pitched tone and negative by a low pitched tone. The audio feature can be disabled when testing relays! The Power Probe III has 2 cool white LED'S that flood the work area with bright light. The housing is sleek and feels great in your hand." (Quoted from product description.)
You can use the Power Probe 3 to test fuses, relays, and to power up and/or ground components simultaneously. They sell expansion kits to improve the functionality of the tester, such as the continuity checker, short detector, the screamer attachment, and extended lead and adapters set. I love to use the Power Probe 3 to diagnose power window issues, bad fuel pumps, alternators, cooling fans, and anything under the dash.
I never recommend probing a wire, however in dire circumstances the sharp needle end easily penetrates into a wire coating allowing for testing while only leaving a tiny hole that can be easily filled with brush on electrical tape.
The best price I found for the Power Probe 3 was on Amazon. If you buy one off a popular tool truck, you will pay around $200. Regardless of where you buy it, its the same tool so why not save a little bit of money? I recommend getting one as soon as possible. It has more than paid for itself over the time I have had it.
The Power Probe 3 also comes in several different colors and designs. Red, Blue, Green, Carbon Fiber, and even a Camo edition. Please don't forget to check out these articles below that I have written about how to understand electricity and use the power probe to test circuits.
Update:: This article is aged. The Power Probe 4 has come out!
Before you begin your electrical testing adventure, you might want to brush up on The Electrical Dictionary and Available Voltage Testing.