Tom's Guide Verdict
With the ability to do the diagnostic basics along with key maintenance issues, Topdon’s TopScan can also dig deep into your car’s performance potential.
Pros
- +
Excellent coverage of automotive diagnostics
- +
Live data
- +
Unique performance indicators
- +
Maintenance items covered
Cons
- -
Transmitter is big and heavy
- -
Some features require subscription after a year
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Size: 3.2 x 2.0 x 1.1 inches
Weight: 2.6 ounces
Live data: Yes
Display: None
Number of keys: None
Bluetooth: Yes
Handheld: No
Warranty: 2 year
The Topdon TopScan may not be one of the cheapest or smallest Bluetooth OBD scanners, but it definitely has the potential to be one of the best. Included is a wide assortment of diagnostic routines from reading fault codes and pre-inspection scrutiny to turning off the check engine light and showing a wide assortment of live parameters.
TopScan comes into its own with a slew of performance and efficiency indicators that can help fine-tune a vehicle but after a year the app requires a subscription. Can this diagnostic gem help keep your car in top form? Read the review to see how it compares to its peers.
Topdon TopScan Review: Price and Availability
At $59, the Topdon TopScan is a mid-priced wireless OBD scanner, on a par with the OBDEleven’s $65 price tag and a significant discount compared to Innova’s CarScan Mobile’s $100. The company makes other DIY scanners as well as professional ones that can cost as much as $4,500.
Topdon TopScan Review: Design
The TopScan’s black OBD transmitter is made of smooth matte plastics, measures 3.2 x 2.0 x 1.1 inches and weighs 2.6 ounces – gargantuan compared to the CarScan Mobile’s or OBDEleven NextGen OBD transmitter. Still, TopScan device easily fits into a toolbox or dashboard glovebox and is easy to insert and remove.
Its three LEDs along the bottom show that the transmitter is powered on, its Bluetooth radio is connected and if it’s linked to the car’s computers. There’s a USB-C connector for firmware updates.
TopScan apps are available for iPhones, iPads and Android systems. It all comes together on the app’s Home Screen with its right-left sliding section for everything from Diagnostics to I/M Readiness to Vehicle Performance. The included Lite version of the app is good for a year, has access to eight key maintenance items including oil changes, a repair guide and service bulletins. That said, the Pro version is a step up with five more maintenance items.
After a year, the Lite version costs $49 a year while the Pro app costs $99. Extensions and specialty items are available to be purchased in the app’s Mall section. If you don’t subscribe, the scanner isn’t bricked and can still do basic OBD work as well as performance testing.
Topdon TopScan Review: Setup
The TopScan’s transmitter is easy to grasp and insert into the car’s OBD port. Its app includes an illustration of the most likely places the connector might be hiding.
Before doing anything else, I registered with Topdon and then plugged in the device. Its Bluetooth LED glowed red to show it’s ready for a connection, followed by blue when it linked with my Samsung Galaxy S20 phone. A moment later it was online with a green LED. The app automatically filled in the serial number and activation code, and all I needed to do was download and install the 49MB download for Subarus.
The TopScan module had a 25 foot range with my phone, allowing me to work in the car’s interior, engine bay or even walk around the vehicle — which was useful for tasks like checking the tire pressure sensors.
Rather than a cursory booklet, Topdon has a good 53-page manual that includes explanations of its unique features along with illustrations. Kudos for putting support contact phone numbers and email addresses at the end.
The TopScan with the Lite version app that I looked at came with a one-year warranty with updates. It can be doubled if you send Topdon an email with your order number.
Topdon TopScan Review: Performance
Able to show and track a variety of live indicators, the TopScan can display your choice of a range of operational parameters, like engine speed, coolant temperature, voltage and ignition timing. It also has the luxury of a check for the neutral safety switch that blocks the starter from engaging if the car is in gear.
The parameters can be graphed singly or up to four at a time for diagnostics and engine tuning. Hot-rodders will love the TopScan because of its built-in Performance Tests, like its 0-to-60 mph and ¼ mile times. Just start the test and it engages when the car starts moving, just have enough open road to do it safely. It lacks a 60-to-0 mph braking test, though.
Able to estimate the engine’s horsepower and torque, the TopScan’s Volumetric Efficiency analysis rates the engine’s performance, something few OBD scanners can do. Happily, the TopScan device and app noticed when I disconnected the under-seat connector for the passenger position sensor.
Topdon TopScan Review: Verdict
Topdon’s TopScan is more than meets the eye for automotive enthusiasts. It can not only find faults and kill the check engine light but check on key maintenance items as well as run an I/M Readiness test before getting the car inspected. It goes beyond the abilities of other scanners in its class with performance and efficiency indicators that can help get 0-to-60 mph times and estimate the engine’s horsepower and torque.
Able to perform tasks that scanners costing 10 times more can’t, the Topdon TopScan can fine-tune a car or just keep it on the road, making it the best $60 automotive tool available.
