About Tachwise

Tachwise is a car-health startup based in British Columbia, Canada. It reads a car's OBD-II port, and Otto, our owl, explains what it finds in plain language: trouble codes, battery health and live data. A free app beta works today with your own ELM327 Bluetooth dongle; the Tachwise device is a prototype, tested in a car, not for sale yet.

What Tachwise does

Nearly every car and light truck sold in North America since the late 1990s has an OBD-II port. Tachwise reads the standard data it shares: trouble codes, including the pending ones a car logs before the check-engine light comes on, and live data such as speed, rpm, coolant temperature and fuel trims. Otto says what each finding means and how soon it needs a look.

The app beta also keeps track of maintenance for oil, brakes, tires, spark plugs, fluids and filters. It estimates when each is due from the distance you drive and the services you log, against intervals you can edit; it doesn't measure the parts. Each car's service history stays with its VIN, can be printed, and can be handed to the next owner as a file.

Where it stands today

  • The app beta works today. It's free and needs no account. Open app.tachwise.com in Chrome on Android, or on a desktop or laptop with Bluetooth, and connect your own Bluetooth Low Energy ELM327 dongle. On iPhone it runs through TestFlight, Apple's app for betas: testflight.apple.com/join/4G4GT6k1. A Play Store beta for Android is on its way.
  • The Tachwise device is a prototype. It is being built to stay in the port and watch the 12 V battery while the car is parked. Our firmware, on development boards, has run in a car, reading live data from the OBD-II port and sending it to the phone over Bluetooth, and the device's own circuit board is ready for production. The first boards go to hand-picked testers from the waitlist. It is not for sale and has no price yet.
  • The waitlist is open and free. Waitlist members get first call to order, and nothing is charged before a device is ready to ship. Join the waitlist to hear first.

Who is behind it

Tachwise was founded by Gerrit van Rensburg, who has an electrical engineering background and grew up in a small town with a racetrack, where he got his first job. He built and bench-tests the device prototype (a Raspberry Pi Pico 2 W with a CAN transceiver), captured OBD-II port traffic on a production car, built the app beta, and wrote the physics-based OBD-II simulator we test with. Tachwise is based in British Columbia.

What else we do

  • Fleets: fleet features for light-duty OBD-II vehicles are planned, not built yet. The fleet waitlist is open, and fleets' answers decide what gets built first.
  • Partners: by enquiry, an OBD-II ECU simulator (an early bench rig, available to selected partners), CAN bus and OBD-II signal analysis, and custom CAN bus devices built to order for trucks, equipment and other machines.

How we write Learn articles

Tachwise Learn answers common car questions. Every article is built on primary sources (regulators, standards, carmakers' service information and battery makers' technical documents), and every claim is checked against its source before we publish. Each article lists its sources with the date we accessed them, and says whether a licensed mechanic has reviewed it. More on how we write.

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