A used Tesla for €35,000.
Everything looks good. Or does it?
SOH shows 92%. The seller is smiling. Three months later: Moisture damage. Battery replacement: €22,000.
SOH alone is blind
SOH only shows capacity. Moisture, dying cells, defective sensors? Invisible.
€15,000 – €25,000
That's how much a Tesla battery replacement costs. Better to know what's really inside beforehand.
Wait 7 days?
Other providers require a full discharge cycle. Impossible when buying a used car.
Special Hardware?
Order rental devices by mail, test, send back. We only need a standard OBD adapter.
Same SOH. Completely different risk.
Two Teslas, both with ~90% SOH on the display. One is perfectly healthy. The other has an active moisture error and 22 Ah CAC spread. SOH shows "green" for both.
This is exactly the risk the TrueHealth Score uncovers — in seconds, not days.
SoHWHAT sees what others cannot.
Developed by RPR Motors — one of Germany's leading Tesla battery repair specialists. Over 250 sustainably repaired batteries, over 500 diagnostics. Not just one number — but 47 parameters that show the full picture.
96 Brick Analysis
Every single cell group is individually checked for capacity and voltage. Weak bricks become visible immediately.
Others only test at the pack level
Moisture Detection
Floodport sensors and water accumulation are read directly. Moisture is the #1 battery killer — and not measurable anywhere else.
No other provider can do this
Weak Short Detection
Detects creeping short circuits in individual cells — before Tesla limits the charge to 50% and value loss occurs.
Prediction instead of surprise
BMS Error Codes
Direct evaluation of all Battery Management error codes — including severity rating. f107, f123, u018, u029 — we explain what they mean.
HV-Isolation & Safety
Measurement of the insulation resistance of the entire high-voltage chain. Critical values below 100 kΩ are detected and warned immediately.
Professional Certificate
Official Battery Health Certificate in 3 levels — for buyers, sellers, dealers, and appraisers. Digitally verifiable.
How it works
Plug. Scan. Know. — Real CAN bus data, 47 parameters.
SOH shows the number.
THS shows the truth.
The TrueHealth Score is the only index worldwide that summarizes BMS error codes, individual cell capacities, moisture, and HV isolation into a transparent score from 0–100.
Why SOH isn't enough
SOH only measures total capacity compared to a new state. It's like measuring a person's health by their body weight alone. Blood pressure? Cholesterol? Organ function? Ignored.
BMS Error Codes 30%
Critical errors like f107 or f123 alone can cap the score at a maximum of 39 — regardless of how good the SOH is.
Cell Health 25%
Individual capacity and voltage balance of all 96 bricks. High spread = weak point.
HV Isolation 15%
Protection resistance of the high-voltage chain. Below 100 kΩ = safety risk. Capped at max THS 49.
Moisture 12%
Floodport sensors and water accumulation. The #1 battery killer — measurable here for the first time.
Capacity (SOH) 12%
Intentionally weighted low. An SOH of 78% on a 7-year-old Model S is completely normal.
Age & Wear 6%
Internal resistance, contactor status, and cycle load relative to vehicle age.
"Aviloo gives you a number. We give you a diagnosis."
THS Rating Scale
How it works — in 4 steps
It couldn't be simpler: Analyze your Tesla in just a few minutes.
Plug in OBDLink
Connect the OBDLink MX+ or vLinker MS adapter using the Tesla adapter cable. Takes 10 seconds. (Note: limitations apply depending on model and adapter — see Hardware section)
Launch the Free App
Open the SoHWHAT app and start the analysis. Within 15 minutes, you'll see the SOH, all 96 bricks live, and HV isolation — all for free.
Check the Results
SOH, brick overview, and HV isolation are immediately visible in the app — free, as often as you like. Moisture, fault codes, and the TrueHealth Score are available with a certificate.
Book Certificate (optional)
Need an official Battery Certificate with TrueHealth Score for buying, selling, or appraisal? Book it directly in the app — from €99.
Supported Models
Tesla Model S · Model X (up to 2021) · Model 3 · Model Y (up to 2023) — see Hardware section for adapter limitations
What you need
Two things: A Bluetooth OBD adapter and a Tesla adapter cable. No special equipment, no rental devices.
🔌 Bluetooth OBD Adapter (model-specific compatibility)
OBDLink MX+
Premium Bluetooth OBD adapter. Fastest chipset on the market, workshop-proven.
- ✓ Model S/X (up to 2021), Model 3/Y (up to 2023)
- ✓ STN2255 — fastest chipset
- ✓ Bluetooth Classic (SPP)
- ✓ iOS + Android
vLinker MS (vGate)
Best value for money. Same functionality, slightly longer connection time.
- ✓ Model S/X (up to 2021), Model 3/Y (up to 2020)
- ✓ Fully compatible with SoHWHAT
- ✓ Bluetooth Classic (SPP)
- ✓ iOS + Android
🔗 CAN Adapter Cable (model-specific)
Model 3 / Model Y
bbfly T6 OBD splitter — connects the OBD adapter to Tesla's CAN bus. Plug & play.
- ✓ Model 3/Y (2017–2024)
- ✓ OBD2 socket → Tesla diagnostic port
- ✓ No disassembly required
Model S / Model X
vhbw OBD adapter — access the diagnostic port under the dashboard.
- ✓ Model S/X (2012–2021)
- ✓ OBD2 socket → Tesla diagnostic port
- ✓ Plug & play
💡 Important: Bluetooth adapters have model-specific limitations — see details for each adapter. The OBDLink MX+ supports more models (Model 3/Y up to 2023), the vLinker MS only up to 2020. ⚠️ No BLE adapters (e.g. OBDLink CX) — only Bluetooth Classic is supported.
* Links on this page are affiliate links. If you purchase through these links, we receive a small commission — the price stays the same for you.
Direct Comparison
Why SoHWHAT offers the most comprehensive battery diagnosis for Tesla.
| Feature | SoHWHAT | Scan My Tesla | Aviloo FLASH | Aviloo PREMIUM |
|---|---|---|---|---|
| App / Live Analysis | ✅ Free | ✅ ~€12 | ❌ | ❌ |
| CAC / Ah Live Data | ✅ Free | ✅ Raw Data | ❌ | ❌ |
| 96 Brick Analysis (Live) | ✅ Free | ✅ Raw Data | ❌ | ❌ |
| Rating & Recommendation | ✅ TrueHealth Score | ❌ Raw data only | ✅ SOH | ✅ SOH |
| Moisture Detection | ✅ From Base | ❌ | ❌ | ❌ |
| Weak Short Detection | ✅ From Expert | ❌ | ❌ | ❌ |
| BMS Error Codes | ✅ From Base | ❌ | ❌ | ❌ |
| HV Isolation Check | ✅ Free | ❌ | ❌ | ❌ |
| Cell Heatmap | ✅ Expert Certificate | ❌ | ✅ Since 2025 | ✅ Since 2025 |
| Official Certificate | from €99* | ❌ | from €99 | from €199 |
| CARA Certification | Planned | ❌ | ✅ | ✅ |
| Multi-Brand | Tesla only | Tesla only | ✅ 50+ Brands | ✅ 50+ Brands |
| Analysis Duration | 5–15 Min | Real-time | ~3 Min | ~4 Hrs |
| OBDLink + Tesla Adapter Cable | ✅ | ✅ | ❌ Aviloo Box | ❌ Aviloo Box |
| Price | App Free | ~€12 one-time | from €99 | from €199 |
Trust & Expertise
Over 20 years of automotive experience. Specializing in Tesla high-voltage batteries since 2018.
Powered by RPR Motors
Developed by Tesla Battery Experts (RPR Motors) — one of the leading independent Tesla workshops in Germany.
Tesla Battery Experts Since 2018
Over 20 years of automotive experience. Specializing in Tesla high-voltage batteries since 2018 — from the Nürburgring to the diagnostic app.
250+ Batteries Repaired
Over 250 sustainably repaired batteries, twice as many diagnosed — "repair instead of discard" is our philosophy.
"We've sustainably repaired more than 250 Tesla batteries and diagnosed twice as many. SoHWHAT is THE tool we always wished for — and now everyone can benefit from our expertise. Important: SOH alone doesn't tell the truth. It's just 1 value of many. SoHWHAT helps you understand — simply and clearly."
Carsten Ohlinger
Founder — Tesla Battery Experts & SoHWHAT
Analyze any Tesla. Free. As often as you want.
The SoHWHAT App is free — no subscription, no trial period, no limitations.
SoHWHAT App
FREE- 96 Brick Live View (Voltage, CAC, SOC)
- SOH & Capacity Display
- HV Isolation & Live View
- BMS Status Live Display
- HV Isolation & Internal Resistance
- Unlimited Vehicles
- No subscription. No cost.
Now you know what's inside. Time to prove it.
For buying, selling, or professional documentation: The SoHWHAT Battery Certificate makes your analysis official, shareable, and digitally verifiable.
Base Certificate
For Buyers & Owners
- TrueHealth Score (0–100)
- SOH & Capacity Analysis
- Moisture Status
- BMS Fault Codes
- 1-page PDF certificate
- Digitally verifiable
Expert Certificate
For Sellers & Professionals
- Everything in Base, plus:
- 96 Brick CAC Individual Cell Analysis
- Weak Short Detection
- HV Isolation & Contactors
- Voltage & CAC Heatmap
- 2-page detailed PDF
- Digitally verifiable
Enterprise
For Workshops & Dealers
- Everything in Expert, plus:
- 3-page Expert Certificate
- 96-Brick Deep-Dive Heatmaps
- White-Label Certificates
- Unlimited Certificates
- Priority Support
This is what you get for your money.
Real certificate from a Tesla Model S with Weak Short — anonymized. This is what professional battery diagnostics looks like.
Frequently Asked Questions
Is the app really free?
The TrueHealth Score and the professional battery certificate (PDF) are optional and start at €99 (launch price). You only need it if you want to officially document the battery condition — e.g., when selling, buying, or for an appraisal.
How much does a certificate cost?
• Base Certificate (
• Expert Certificate (€249): 2-page PDF with 96-brick heatmap, Weak Short Detection, and internal resistance. For sellers and professionals.
• Enterprise (from €99/month): Unlimited certificates with white-label and 3-page expert report. For workshops and dealers.
Every certificate is digitally verifiable — buyers can check authenticity via QR code.
What hardware do I need?
Unlike most manufacturers, Tesla does not expose deep BMS data via the standard OBD2 protocol — even if a port is physically present. Without the correct adapter and cable, battery data cannot be accessed. A cheap ELM327 adapter will not work.
Important limitations:
- OBDLink MX+: Model S/X (up to 2021), Model 3/Y (up to 2023)
- vLinker MS: Model S/X (up to 2021), Model 3/Y (up to 2020) — filters out important CAN IDs on newer vehicles
How long does a test take?
No driving required, no discharge cycle, no 7-day waiting period. Just plug in the OBDLink, open the app, done.
What's the difference between SOH and THS?
The TrueHealth Score (THS) considers 6 categories: BMS fault codes, cell health, HV isolation, moisture, capacity, and wear. A Tesla with 92% SOH can have a THS of 34 — because it has a hidden moisture problem.
Which Tesla models are supported?
⚠️ Note adapter limitations: The vLinker MS only supports Model 3/Y up to 2020, while the OBDLink MX+ supports up to 2023. Model S/X are supported by both adapters up to 2021.
Additional vehicles (VW MEB platform: ID.3/ID.4, BMW iX/i4) are in development.
Is SoHWHAT better than Aviloo?
For Tesla, SoHWHAT offers a significantly deeper analysis: 47 parameters instead of ~15, individual brick capacity (CAC), moisture detection, Weak Short Detection, and the TrueHealth Score.
The biggest difference: With Aviloo, you pay from €99 before you see any result. With SoHWHAT, you analyze your Tesla for free and in real-time. You only order the certificate if you need it.
Can I test a used Tesla at a dealership?
Is there an Android version?
What happens with my data?
Questions? We're here to help.
Whether it's technical questions about the app, enterprise inquiries, or feedback — just drop us a message.
Ready to learn the truth
about your battery?
SoHWHAT is available in the App Store. Android coming soon.