Black Friday Event Innova 5420: $99.99 · Free shipping –
Innova

BLACK FRIDAY

$50 off the 5420 the tester with a patented swivel head
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Stop buying parts you didn't need. Power the part, see if it works, then decide. $99.99 for Black Friday, was $149.99. Free gifts while units last.

  • Free shipping
  • Free tool pouch
  • No subscriptions
  • Computer safe
The Innova 5420 reading 12.6V over a car fuse box

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Black Friday: Innova 5420 PowerCheck

Powered circuit tester. Send power or ground to any component and see the voltage that actually got there. Now $99.99 for Black Friday.

  • Innova 5420 PowerCheckInnova 5420 PowerCheck$149.99$99.99
  • Innova tool pouchInnova tool pouchLimited units$23.52Free
  • Extended 1-year warrantyExtended 1-year warranty$29.00Free
  • RS2 app accessRS2 app access$99.00Free
  • Free shippingShipping$10.00Included
$99.99 $149.99
Add to cart

You save $50.00 · Gifts applied at checkout · No promo code

What it does: it proves the part works before you buy a new one.

A test light only tells you voltage is there. The 5420 clips to your battery or power outlet and powers the component itself, so you know if it's the part or the circuit.

A mechanic testing a circuit under the hood with the Innova 5420

1.Power it up

Supply power or ground on demand to switches, relays, fans, pumps and lighting. If it turns on, the part is good.

A technician probing door wiring with the Innova 5420

2.Read the real voltage

The screen shows the voltage that reached the circuit. Choose 3V, 5V or 12/24V, for passenger and heavy-duty vehicles.

A technician testing door wiring with the Innova 5420

3.Stay computer safe

An automatic-reset circuit breaker protects sensitive modules, and the long cord reaches anywhere on the car.

5420 vs a test light: one checks, one proves.

A test light glows when voltage is there. The 5420 tells you how much, then powers the part so you see it work.

Innova 5420 compared with a basic test light
 Innova 5420Test light
Innova 5420 PowerCheckBasic automotive test light
Shows power is thereYesYes
Shows the actual voltage0.1–200 VDCNo
Powers the component3V, 5V, 12/24VNo
Grounds the componentYesNo
Polarity at a glance+ / − LEDsNo
Overload protectionAuto-reset breakerNo
Reach20 ft of cableShort lead

Built for more than one job: if it runs on 12V, test it.

A hand probing a car fuse box

Blown fuse

Lights or windows quit? Check the fuse box without pulling every fuse.

Trailer tail lights lit up

Trailer lights

Find whether it’s the bulb, the ground or the wiring.

A mechanic holding a fuel pump assembly

Fuel pump

Power the pump directly to see if it runs.

A mechanic holding a radiator cooling fan

Electric fan

Spin the cooling fan on the bench or in the car.

Power window switches on a car door

Window regulator

Power the motor to check it before buying a new one.

A camper van parked by the sea

RV power

Confirm power and ground on 12V and 24V systems.

Quick answers.

No. The Black Friday price and the free gifts are applied automatically when you tap Add to cart.

Black Friday

$99.99 for Black Friday. While units last.

When the sale ends, the price goes back to $149.99.

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Free shipping · Free tool pouch · No subscription, ever

From 5420 owners: in their own words.

4.5out of 5

Based on 71 global ratings on Amazon

ADAmanda and DaveAmazon · Nov 5, 2022
Amazon Vine review

Excellent Powered Circuit Tester Tool

A tool like this is extremely useful in vehicle electrical repair and diagnoses. Not only is this a digital volt meter with polarity indication, it is also able supply power or ground to a circuit or component with a press of a switch.

The tool comes packaged in a plastic tray inside of a thin box. Included with the tool is 2 different length probes, battery power adapter and manual. The tool has a cigarette lighter plug attached to it so you will need to use the adapter for battery connection. This tool has an adjustable angle for the probe which is achieved by twisting the end and it angles downward. This is a convenient option if you are doing fuse box work as you can see the screen while working downward.

Powering voltage from the tool is achieved by pressing the rocker switch up or down for positive or negative respectively. There is also a slide switch to adjust output voltage from 3, 5 or 12 volts, which is handy if working with low voltage reference circuits in automotive.

All in all this is a very comparable tool to a well known brand name "probe" for a bit less money. I own that other brand probe as well. I feel like the quality is a bit lower on this one but not by much. For the price difference between the two, this INNOVA tool is well worth it. 5 stars.

Photo of the Innova 5420 posted by Amanda and DavePhoto of the Innova 5420 posted by Amanda and DavePhoto of the Innova 5420 posted by Amanda and Dave
GWGenevieve WeissAmazon · Oct 5, 2025
Verified Purchase

Fantastic diagnostic tool

Fantastic tool that I should have bought years ago. I got it on sale for well below the price of the other big brand names, and it's lived up to my expectations plus some. The pivot head makes it a lot easier to use under the dash and the voltage switch makes testing for wiring connectivity much easier. Highly recommend for any technician who does vehicle electrical repairs regularly

DDustinAmazon · Oct 19, 2022
Amazon Vine review

Works great!

I got this to diagnose a window issue I have been chasing in my car and its just what I needed. The multiple prongs and flexible head made it easy to get power to the window motor to check it. Easy to use feels well built. A must have for any gear head, perfect for the shop or at home to get power where you need it.

Photo of the Innova 5420 posted by Dustin
TETech ExpertAmazon · Jul 13, 2023
Verified Purchase

Love it!

I never knew I've been missing such an important tool. For the longest time I've dismissed these power probes as nothing more than a gimmick not fully realizing how they work. Prior to this using multimeter was my go to, but this tool makes things so much easier and quicker to diagnose that it's a whole new category in itself. I bought this version because it has 3/5/12V options to send power, while others only did the 12V. To me that seemed important because many sensors/solenoids, run on lower voltage than 12V and you wouldn't want to fry them, or get misleading results from sending the wrong voltage to those parts. If you are on the fence about getting a power probe and you do automotive work quite often, I'd say get it, you'll thank yourself that you did.

JLJP LambiaseAmazon · Feb 16, 2026

🛠️ Because Real Men Don’t Guess

This tool is so powerful… it practically grows chest hair just sitting in the toolbox.
Because real men don’t wonder what’s wrong with a circuit.
We apply power. Directly.

A 20-foot cable — because commitment issues are for amateurs.
Backlit LCD display — so you can see results even in the darkest corners of your soul
And a 45-degree swivel probe head, designed to reach places lesser tools simply can’t

If you want to check a fuses, you get an instant readout.
If the current passes, it passes. If it doesn’t… it’s out.
We don’t blame the wiring. We don’t blame the weather.
We replace it.

This isn’t just a tester. It’s a fuse inspector. A relay commander. A continuity enforcer. A multimeter substitute.
All in one tool. Because carrying five tools is inefficient… and inefficiency is weakness.

Photo of the Innova 5420 posted by JP LambiasePhoto of the Innova 5420 posted by JP LambiasePhoto of the Innova 5420 posted by JP Lambiase
DHDannie H.innova.com · Feb 21, 2026
Verified buyer

Just WOW.

i wish i had this 40 years ago it would have saved me alot of time. now i have the 35A and the 5610 with a 3380 plus my old 3100j in my hands now. just WOW

RCRick and CarolynAmazon · Oct 17, 2022
Amazon Vine review

Quality Automotive Tool

This is a nicely designed device to track down automotive electrical problems. It can be powered by the car’s battery or its cigarette lighter. It will tell you about the condition of the battery and alternator as well as help determine the connection to many other components such as the car’s fuses, fans, and lighting. The head tilts to permit use in tight situations, and LEDs provide light to assist in the testing. A cigarette adapter is included to assist with in-car testing. In my opinion, this tester is well made and simple to use.

Photo of the Innova 5420 posted by Rick and Carolyn
MKMichael K.innova.com · Jun 9, 2026
Verified buyer

Nice tool to add to the arsenal

LLisaAmazon · Nov 10, 2022
Amazon Vine review

Works great

This can be used for multiple items. Love that it can be used on a vehicle. Works on 24 volt to 6 volt. Easy to use.

Photo of the Innova 5420 posted by Lisa
DDavohuntAmazon · Oct 22, 2022
Amazon Vine review

GREAT VOLTAGE READER

Very simple to use doesnt take much to figure it out It helps narrow down where you not getting power from point A to point B.
Excellent tool for keeping on my toolbox 🧰

Photo of the Innova 5420 posted by Davohunt

Real reviews of the Innova 5420 from Amazon and innova.com, copied word for word. Photos posted by the reviewers.

Innova Innova 5420
Innova 5420: $99.99
Black Friday –
Innova 5420
$50 off Black Friday
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