Test a Prius battery before you buy
Plug a Bluetooth LE OBD-II adapter into a Toyota Prius and read the hybrid battery from your iPhone: every block's voltage and resistance, straight from the car's battery computer, and a plain verdict.
Coming soon to the App StoreFor Toyota Prius 2004–2015. Needs a Bluetooth LE OBD-II adapter (not included).
What the hybrid battery test reads
Every block's voltage
All 14 battery blocks at rest, the spread between the highest and lowest, and the weak blocks named.
Load step
Turn the A/C to max for 60 seconds in READY. A weak block sags further than the rest when the pack works, which a rest read can't show.
Internal resistance
Each block's resistance as the battery computer measures it, with any block that stands out from the pack highlighted.
Battery history
The stress counters the battery computer keeps over the pack's life, in plain words: how often it ran too hot, too low or too high.
A certificate you can show
A one-page PDF with the car, the date, the verdict and the block map, to share between buyer and seller.
For hybrid shops
The Shop unlock puts your shop's name, logo and phone on certificates, with the customer's name and full VIN, and exports every test as CSV.
How it works
- Plug a Bluetooth LE OBD-II adapter into the port under the dash, to the left of the steering column.
- Press the power button with your foot on the brake until READY lights.
- Open the app and tap Test a hybrid battery. The free check confirms your adapter reaches Toyota's battery computer before you pay anything.
- Read the battery at rest (about 10 seconds), add the optional 60-second load step, and get the verdict: healthy, weak blocks, or failing.
No adapter yet? The app includes a demo Prius that runs through the same reader the app uses on a real car.
Free, Lifetime and Shop
| Free | Lifetime ($14.99 once) | Shop ($34.99 once) | |
|---|---|---|---|
| Adapter and battery-computer check | ✓ | ✓ | ✓ |
| Generation, VIN, pack voltage and current | ✓ | ✓ | ✓ |
| Demo Prius | ✓ | ✓ | ✓ |
| Verdict, block map, resistance, load step | — | ✓ | ✓ |
| Battery history (stress counters) | — | ✓ | ✓ |
| Certificate PDF | — | Personal | Branded: shop name, logo, customer, full VIN |
| Saved cars | 1 car, last test | Unlimited | Unlimited |
| CSV export | — | — | ✓ |
One payment each, no subscription. Restorable on any device with the same Apple ID. US prices.
Supported cars
Toyota Prius 2004–2015: block voltage, internal resistance and stress history.
RAV4 Hybrid, Camry Hybrid and newer Priuses are coming after real-car testing. We only offer a car once we've read one ourselves.
Read-only and private
Hybrid Battery Test only reads. It never writes to your car, clears codes or changes the battery fan. Every test stays on your iPhone: no account, no servers, no analytics.
Which adapter?
iPhone can't use the cheap "Bluetooth OBD2" adapters that only pair with Android, and some clones can't switch to Toyota's battery computer. See the adapter guide.