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Innova 3721 Battery and Charging System Monitor
Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
- Select the return method
- Ship it!
Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
- Select the return method
- Ship it!
Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
- Select the return method
- Ship it!
Purchase options and add-ons
Brand | Innova |
Power Source | Battery Powered |
Style | 12-volt |
Color | Limited Edition |
Item Weight | 0.2 Pounds |
About this item
- Easily plugs into vehicle’s cigarette lighter or power receptacle to monitor battery and charging system voltage
- Designed for 12-volt negative ground systems
- LCD displays measured voltage with a bar graph to indicate battery charge level
- Color-coded LEDs quickly identify battery’s charge status
- Head pivots for easy viewing and angle adjustment
Customer ratings by feature
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This Item Innova 3721 Battery and Charging System Monitor | Recommendations | dummy | dummy | dummy | dummy | |
Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | |
Price | $20.10$20.10 | -38% $22.69$22.69 List: $36.60 | $17.95$17.95 | $32.10$32.10 | $13.99$13.99 | $16.99$16.99 |
Delivery | Get it as soon as Sunday, Mar 17 | Get it as soon as Sunday, Mar 17 | Get it Mar 19 - 22 | Get it as soon as Sunday, Mar 17 | Get it as soon as Sunday, Mar 17 | Get it as soon as Sunday, Mar 17 |
Customer Ratings | ||||||
Accuracy | 4.5 | 3.8 | — | 4.1 | 4.7 | 4.2 |
Easy to use | 4.8 | 3.8 | — | 4.3 | — | 4.6 |
Easy to read | 4.7 | — | — | 4.5 | 4.8 | 4.4 |
Sold By | Amazon.com | Amazon.com | motohousemx | Amazon.com | Chanketch | TONNY TOOLS |
power source | Battery Powered | Hand Powered | Battery Powered | Battery Powered | Battery Powered,electric | Corded Electric,battery Powered |
measurement type | — | Multimeter | — | Multimeter | Voltmeter | — |
style | 12-volt | Standard | — | 3320 | Digital | 12V |
weight | 0.2 pounds | 0.19 pounds | — | 0.5 pounds | 3.52 ounces | — |
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Product Description
The INNOVA Battery and Charging System Monitor displays the condition of your battery and charging system instantly. It protects the engine computer and 12-volt accessories from damaging surges when jump starting or recharging. Easily plugs into the vehicle's cigarette lighter or power receptacle to monitor battery and charging system voltage. The LCD screen displays the measured voltage with a bar graph to indicate battery charge level and the color-coded LEDs quickly identify the battery's charge status. The head pivots for easy viewing and angle adjustment.
From the brand
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How we got our start
Located in Irvine California since 2012, It's a solutions company that has best in class data taken directly from top manufacturers.
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Carscan: From Diagnosis To Fix
The most comprehensive automotive OBD2 code reader and scan tool solution from diagnosis to fix, with the push of a button.
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Why we love what we do
For over 30 years Innova products have been designed and developed in California by certified ASE Master Technicians.
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Award-Winning
Innova is consistenly recognized for its total solution tools for automotive repair and use.
Product information
Brand | Innova |
---|---|
Power Source | Battery Powered |
Style | 12-volt |
Color | Limited Edition |
Item Weight | 0.2 Pounds |
Item Dimensions LxWxH | 10 x 1 x 6.5 inches |
Product Dimensions | 10 x 1 x 6.5 inches |
Item Weight | 3.2 ounces |
Manufacturer | Innova |
ASIN | B000EVWDU0 |
Country of Origin | China |
Item model number | 3721 |
Customer Reviews |
4.5 out of 5 stars |
Best Sellers Rank | #32,248 in Automotive (See Top 100 in Automotive) #56 in Battery Testers |
Is Discontinued By Manufacturer | No |
Assembly required | No |
Warranty Description | 1 year limited |
Batteries required | No |
Included Components | BATTERY & CHRG SYSTEM MONITOR |
Warranty & Support
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From the manufacturer
INNOVA 3721 Battery and Charging System Monitor
The INNOVA Battery and Charging System Monitor displays the condition of your battery and charging system instantly. It protects the engine computer and 12-volt accessories from damaging surges when jump starting or recharging. Easily plugs into the vehicle's cigarette lighter or power receptacle to monitor battery and charging system voltage. The LCD screen displays the measured voltage with a bar graph to indicate battery charge level and the color-coded LEDs quickly identify the battery's charge status. The head pivots for easy viewing and angle adjustment.
Top Brand: Innova
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Customer reviews
Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.
To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzed reviews to verify trustworthiness.
Learn more how customers reviews work on AmazonCustomers say
Customers like the readability, performance, value, brightness, and ease of use of the electric circuit testing device. They mention that the flexible head makes the large display easy to read, and the LCD is clear with bright blue backlight. They also appreciate the simple instructions and the ability to check your charging system. Customers are also happy with reading, and battery monitor. However, some customers differ on quality.
AI-generated from the text of customer reviews
Customers are satisfied with the performance of the electric circuit testing device. They say it is a simple and very useful device that works well with relatively accurate data. It works instantly, as long as the accessory is inserted. Customers are also impressed with the accuracy and helpfulness of the device.
"This works well...." Read more
"...In conclusion, this is a useful tool and I do not like to have it plugged in all the time but if you doubt your battery's health plug it in and get..." Read more
"...and now I can monitor battery voltage and charging status Works very well." Read more
"...used twice since purchasing, the item seems to be accurate and it works well. Quality control issues have been noted by others, but so far, so good." Read more
Customers like the battery monitor. They say it is very handy at checking system voltage, and it helps to identify low battery power in their vehicle and travel trailer. The monitor also indicates the battery voltage when the motor is not running, and is very convenient to use. Customers also say that it measures exactly the voltage real time, and has a great volt readout display. They mention that the product does exactly what it says it will do, and that it helps them monitor their auxiliary battery.
"This product allows me to monitor my auxiliary battery on my 2022 Toyota Sienna...." Read more
"...however reads both voltage and current.... same accuracy... I have either in all my and siblings vehicles... I recommend my 1st choice..." Read more
"Good for keeping track of battery in RV" Read more
"...Less guess work and distraction... I also like the estimated charge level icon... while it doesn't seem to be very consistent I'm not sure if it's..." Read more
Customers find the electric circuit testing device easy to use. For example, they say it's simple to plug into any cigar lighter, comes with excellent instructions, and is easy to decipher. Some say it is a quick one-hand operation and that it is one of the best auto tools they have ever bought.
"...It is also incredible easy to understand. The included instructions are written for drivers not auto mechanics." Read more
"...It's very easy to use and accurate.My issue began when it fell apart in the cigarette lighter socket...." Read more
"...I found it to be very accurate and easy to use. However I would not leave it in the car ever...." Read more
"...It does exactly what it says it will do. Very convenient and easy to carry around...." Read more
Customers are satisfied with the value of the electric circuit testing device. They say it is awesome for the money and saved them hundreds of dollars.
"...This is a good buy at $20 so get it plug it in and enjoy the readings." Read more
"...]) but it is worth every penny to have the voltmeter in a package that plugs in your car and..." Read more
"...LED.. reads to 1/100 of volt.. 4 digits... ie.. 12.65... good value for the money... has both std...." Read more
"...Damn good for the cost of this thing. The head swivels nicely, stays in place so I always have a good angle to view the readings while driving...." Read more
Customers are satisfied with the reading of the electric circuit testing device. They mention that it is very accurate, has good measurement accuracy, and is accurate to two decimal places. Customers also appreciate the high reading and the fact that it has two units past the decimal place.
"...thing but I do understand the rest of it and it is reliable and pretty accurate though the only thing I know to compare is the typical readings you..." Read more
"...however reads both voltage and current.... same accuracy... I have either in all my and siblings vehicles... I recommend my 1st choice..." Read more
"Although only used twice since purchasing, the item seems to be accurate and it works well...." Read more
"...The device was giving me very accurate information and if I hadn't continued to the dealer I would have had real problems. My car was ok...." Read more
Customers find the readability of the electric circuit testing device to be excellent. They mention that the flexible head makes the large display easy to read, regardless of the location of the product. The swivel head makes it easy to look at, and the LCD is clear and bright. The readout is large, clear, and well illuminated. The monitor is really awesome in that the head folds up and down.
"...multimeter... small... compact.. easy to read... bright LED.. reads to 1/100 of volt.. 4 digits... ie.. 12.65... good value for the money... has..." Read more
"...Fits snugly in the lighter socket, hinge is smooth, display is easily readable. Made in China. Recommended." Read more
"...Warning lights function well.Some things to note when using this tester: Standard voltage of a 12 volt battery is 12.6 volts...." Read more
"...The display is lighted and easy to read, it folds for sight adjustment so it can be angled towards the driver...." Read more
Customers like the brightness of the electric circuit testing device. They say the readout is large, clear, and well illuminated. The display is backlit all the time, making it easy to view in all lighting conditions. The green-yellow-red lights are OK, and the trip point for a battery is green- yellow. Customers also like the LED status light, which can be seen from a distance.
"...multimeter... small... compact.. easy to read... bright LED.. reads to 1/100 of volt.. 4 digits... ie.. 12.65... good value for the money... has..." Read more
"...The backlit display is clear and easy to view in all lighting conditions. For nighttime driving the backlight may be a bit too bright, however...." Read more
"...in the sun so today when I tried to use it, I noticed the screen was pitch black like all the ink inside the display had leaked and nothing was..." Read more
"...This is a quick one hand operation with LEDs and backlit large numeric display. No reading glasses needed...." Read more
Customers are mixed about the quality of the electric circuit testing device. Some mention it's well made, very good value, and reliable. However, others say that the tip easily unscrews and falls apart in normal occasional use.
"...graph part of this thing but I do understand the rest of it and it is reliable and pretty accurate though the only thing I know to compare is the..." Read more
"...Quality control issues have been noted by others, but so far, so good." Read more
"...Help me out here. The tip so easily unscrews it falls apart in normal occasional use and falls apart in the cigarette lighter socket?..." Read more
"...Now I get exact voltage readout.Very well made and sturdy device...." Read more
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First, let me say that all that matters is the voltage reading and the green, yellow and red led indicators on it are useless and pointless. Now, let me say that the bar graph to the right of the voltage reading and the symbols above that are also useless and pointless. Once you understand the voltage numbers that you see you will find this to be a very useful tool and if you are willing to read further, I will attempt to explain the voltage readings you will get. If you do not want me to bore you with details, all you need to do is plug this in and get 12 to 13V while the car is not running and get 13.5V or more while the car is running.
Checking your battery's health:
A lead acid car battery is typically 12V but a healthy fully charged 12V battery that has no load connected to it will give you a reading of 13V or a little over that. A car battery under normal load (not cranking the engine but have the ignition key turned to on without the car running) should not give you a reading of less than 12V. If you plug this meter to your receptacle and turn the ignition key to on (engine not running) and you get a reading less than 12V, your battery needs to be charged soon. Most cars will not crank "happily" if the battery voltage is less than 12V before you start cranking. Based on this, if you want to see how is the health of your battery, you should get in the car after the car has been off for more than 12 hours, turn on the ignition (do not start the car) and take a reading. The reading should not be less than 12V and the higher it is the better the battery is doing. You should not expect that you will see the "fully charged, no load" reading of 13V because unless you have an antique, your car uses battery power even when the ignition is off for many things including waiting for you to press the buttons on your keyfob or turn on the dome light when you come close to your car door with keyless entry. The truth is that the best indicator of your battery's health is how fast the battery discharges under load but you will not know how much "load" is on your battery while you are taking the voltage readings so it is hard to explain this in a review.
Checking your charging system (alternator) health:
When your car is running, the alternator is charging the battery. To do so, it has to provide higher voltage levels than the battery itself so the battery can be charged. A typical alternator will provide 14V to 15V while the car is running but alternators are not like generators and they need to keep adjusting the output voltage with a circuit called the regulator because the engine revs are rarely constant. Because of this, when you take voltage readings while the car is running, you may see the voltage move up and down and seem unstable. However, you should not see the voltage jumping up and down more than a few tenths of a volt constantly. So to see if your car's charging system works well, plug in this meter and start your car. You should get a reading close or a little more than 14V but generally readings between 13.5V and 15.0V while the car is running are good and this means that your car is charging the battery. Having said that, contemporary charging systems may monitor the amount of amperage that the battery is drawing and stop charging the battery because it is fully charged. In this case, you will see readings of less than 13V while the car is running but that will be short lived because the battery will not be fully charged for long and the voltage should jump back up to start charging it again.
In conclusion, this is a useful tool and I do not like to have it plugged in all the time but if you doubt your battery's health plug it in and get some readings. Don't let the led lights get you dizzy because they mean nothing. To have any meaningful indication from the led lights and the bar graph, this unit would need to be calibrated to your specific car. You could get the same readings from a digital multimeter or even this inexpensive voltmeter ( Green Dc 4.0-30v LED Panel Digital Display Voltage Meter ) but it is worth every penny to have the voltmeter in a package that plugs in your car and swivels. As for my battery, I was getting readings of 11.6V every morning and if I would leave the car at rest for more than 24 hours, it would go below 11V. So I replaced it myself and did not trust the dealerships batteries for the temperatures in the northeast so I got one that was made for colder climate.
Works very well.
Top reviews from other countries
I compare the voltage on the Innova 3721 with my Multimeter and it's exactly the same.
Great product