Redefining the Automotive Test Light

Redefining the Automotive Test Light

Why did we want to redesign the automotive test light?

During daily use of the car, a variety of circuit problems can occur in the car, in occussion, the brake lights are not working, or in other time, the charging system or ignition have problem. Well, these problems are probably occurring just beacause of a poor connection in the car's wiring system. As such , you'll need a simple automotive test pen can quickly help you to determine where the problem is !

Following conditions can be used to test the fuse or the circuit line with test light 

● Fog light not bright

● Horn not sounding

● Headlights not lighting up

● Car not igniting

● Air conditioning not working

● Sunroof not opening

● Cigarette lighter not working

● Reverse light not working

However, when we investigated the market, we found that the automotive test pen had not been upgraded for a long time.

We tested almost all of the test light automotive available on the market and found that these pens are generally not very good experiential to use.


Generally rough workmanship, the chip is exposed outside, no design aesthetics to speak of.

Weight or size.

Either too heavy or too small for a good grip


The function is commonly simple. No in-depth consideration of the user's actual requirements for use


The incandescent pen can easily burn out some sensitive and expensive electronics inside the car (such as ECU))

As a frequently used tool, the contrast between the poor experience of using these products and the widely used scenario is too great, which make us feel very necessary to do a new upgrade and transformation of the automotive test light. So in early 2021, we launched a project to work on this.

Although it looks like a simple test pen, we still gathered the best designers and engineers team in the company. The team put in a lot of passion and effort over the next year or so.

Through continuous testing of products on the market, and discussing repeatedly with a dozen experienced auto mechanics.

Design, development, molding, sampling, testing, optimization. Constantly optimizing, We finally made this very awesome test pen on the market today .

First of all, regarding the appearance of the test pen.

About the size: the whole pen is 48 inch long, which is a just right length. Because if the length too long , it is hard to locate accurately, too short, then it is hard to grab.

about the weight: the whole pen weighs 60 grams, approximately the weight of a fountain pen, this weight will not make your hands sore during long time of use.

Secondly, in terms of the structure of the product, we have made the following improvements.

Removable bulb

The bulb most commonly used in automobiles was chosen. If the pen is used carelessly, excessive current burns out the bulb, it can be easily purchased and replaced through the local auto tool store.

Removable stainless steel probes

We choose stainless steel to make the probe, because it can not only prevent rust, but also ensure the hardness of the probe, longer service life.

In addition, the detachable probe can be replaced after a setback or damage, and is also convenient for storage.

1.2M long soft wire

This length meets most scenarios. The reason for using soft wire instead of coiled wire is that the stretching force of coiled wire will make the clips fall off, and the radius of use is not as good as soft wire.

Bigger Alligator Clips

Our alligator clips are 35% larger than regular alligator clips on the market, providing a larger contact area and more powerful clamping force for more secure contact with the test power source.

Auxiliary probe

Auxiliary probes make it easy to access power in locations where clips cannot be used

Convenient to connect across the relay contact terminals

Lastly, we have also made innovations in product features to provide users with a better experience in the use process

3 working modes.

According to user feedback, we creatively added the 3 working modes of the power meter pen.

Mode 0: Fast Test Mode

This mode is the most commonly used mode, we can easily determine whether the power is on, positive and negative, voltage readings, and through the light bulb brightness to understand the strength and frequency of the current

Mode 1: Computer-Safe mode

In this mode, the incandescent light of the stylus is off, and this mode is crucial.

1、When testing the ECU computer circuit, the LED mode can effectively prevent the ECU from being burned out by excessive flow   

2, in dim light places, this mode to prevent the bright light of incandescent lamps on the eyes

Mode 2: Bulb Mode

Bulb mode is necessary when we need to judge the strength of the circuit current or judge the frequency of the pulse current

Also our LED display shows the frequency of the pulsating current. It is very useful for users to test the ignition pulse signal of ECU and the pulse signal of fuel injector.

Our SigmaProbe SP1 pen can be used in a wide range of automotive circuit testing.

 The use of this pen is also a very wide range of scenarios, its measurement range is 5 - 30V, allowing it to be used not only in cars and motorcycles, but also in trucks, yachts and all other 12V and 24V vehicles, including new energy cars Tesla (in addition to the power battery, Tesla's circuit is also 12V)

That's about it for the SigmaProbe SP1. I'm sure some people will ask how expensive such a stylus must be.

The team discussed during the pricing process that the price of an ordinary pen on Amazon is around $23.99, so we can sell such a good product for at least $39.99, right?

We thought about it for a long time, and although we invested a lot in making the product, we wanted our product to bring convenience and value to more people. So ultimately our pricing was set at


The automotive test pen is not only a must-have tool for auto mechanics, but even a must-have tool for every car owner. I believe the value it brings will go far beyond the product                        

Get it Now!  

Retire Your Old Automotive Test Light

Want to know the problem with your vehicle’s charging system or ignition? Or do you want to know why the brake lights aren’t working? Well, these problems are probably occurring because of a poor connection in the car’s wiring system. As such, you’ll need a unique tool to determine where the problem is!

A test light is a simple device that can tell you if power or ground is present at a particular circuit or fuse.

What is a test light for a car?

What is the purpose of a test light automotive?

How do you properly use a circuit tester (test light automotive)?

What is the difference between a test light and a multimeter?

Let's come to another quesiton: Which is the best automotive test light suit for me ? So I'll be able to detect all my car's wiring problems in no time.

1、Replace your incandescent test light with a digital LED test light

Using a test light to check for circuit voltage is a tried-and-true diagnostic method. But if you probe a computerized circuit with your old incandescent test light, you can fry some sensitive and expensive electronics. 

Since almost every circuit in a late-model car is controlled by a computer, it’s best to say goodbye to your old test light and invest in a computer-safe test light. These don’t pull any power from the tested circuit. Instead, they plug into the cigarette lighter. 

So, Invest in a computer-safe test light and retire the old incandescent test light. The old one can damage sensitive electronics in your car.