Battery Health Monitoring
Track your high-voltage battery at the deepest level available outside a Tesla Service Center.
- 96 individual cell voltages — detect weak cells before they affect range.
- Supercharging Analysis — When the T800 Box stays powered during charge sessions, it can capture high-power charging context such as thermal behavior and charging profiles.
- Pack voltage, current, and internal resistance (calculated from V/I step changes).
- Nominal capacity tracking (SOH) — know your true remaining kWh.
- Cell spread trends — the single best predictor of pack degradation.
- Module temperature distribution across 4 channels.
Air Suspension Health
T800 monitors Tesla air suspension using pressure, ride-height, and actuation evidence rather than a single pump heuristic.
- Air pressure across all 4 corners (FL/FR/RL/RR).
- Height level and relative ride-height signals for commanded changes vs. passive drift.
- Deep-idle drift and intra-day asymmetry analysis.
- High-current actuation evidence separated from HVAC, thermal-management, and charging confounds.
Customer-facing suspension alerts remain under active validation. The goal is to ship a monitor that is conservative and credible, not one that guesses.
Professional Inspection Mode
Turn your T800 Box into a mobile diagnostic station. Buying a used Model S/X, verifying a repair, or appraising a trade-in — temporarily power the T800 Box from the car and get a professional-grade assessment on the spot.
- Instant Deep Scan — Full system health check in under 60 seconds.
- Live Data Stream — Watch real-time valve duty cycles, coolant flow, and motor stator temps.
- Truth Verification — Compare reported BMS capacity with real-time calculated health. Is the seller’s “95% battery” claim real?
- Service Validation — Verify that repairs (like a new 12V or air pump) were performed and configured correctly.
One inspection can reveal problems that a test drive never will.
12V Battery Watch
The #1 cause of unexpected Tesla roadside failures. T800 monitors it continuously:
- Sleep voltage baselines — identify aging before it’s critical.
- DC-DC converter output current — detect parasitic drains.
- Alert threshold at <11.5V — weeks before you’d notice symptoms.
Thermal Management System
The cooling system protects your battery and motors. T800 watches every component:
- Coolant temperature (battery inlet/outlet)
- Pump and valve duty cycles across 7 channels
- Battery heater power and efficiency (peak 9.65 kW)
- Front and rear motor stator temperatures
- Inverter PCB and DC capacitor temperatures
- Coolant temperature stability analysis
A failing water pump or stuck valve can cause $1,500+ in motor/battery damage. T800 detects anomalies in pump duty and coolant flow before they cascade.
Charging Health
Understand exactly how your Tesla charges — at home and at Superchargers:
- AC charging rate, power consistency, and line voltage stability
- DC Supercharger current and line loss analysis
- Charging temperature rise profiles
- Charge efficiency over time
Energy Efficiency
Know where every kWh goes:
- Drivetrain efficiency maps by RPM and power output
- Motor RPM ripple analysis (early indicator of bearing wear)
- Consumption breakdown: driving vs. HVAC vs. Sentry Mode vs. standby
- Cold-weather penalty quantification
Predictive Alerts
Validated alerts use 4-level escalation with hysteresis:
- Normal — all metrics within range
- Observe — single-day breach, monitoring closely
- Warn — persistent anomaly (3+ of 7 days)
- Alert — multi-metric confirmation with trend support
Every alert includes a confidence score and plain-language recommendation for what to do next. Monitors still in validation stay visible in the report without driving customer-facing alerts.
Daily Health Report
Six specialized monitors generate a unified daily report:
| Module | Key Metrics |
|---|---|
| Battery | Capacity (kWh), cell spread (mV), internal resistance (mΩ) |
| Suspension | Deep-idle runtime (s), drift CMR (raw/h), intra-day asymmetry |
| 12V System | DC-DC efficiency (%), sleep voltage (V), static power (W) |
| Thermal | Coolant max (°C), stator max (°C), pump overload (min) |
| Charging | AC power (kW), charge rate (%/h), temp rise (°C) |
| Efficiency | Drivetrain efficiency (%), consumption (Wh/km) |
Professional Sell Report
Generate a comprehensive PDF covering your vehicle’s complete monitoring history. For buyers, a T800 report is evidence — not just a claim — of how the battery, suspension, and drivetrain have behaved over time.
T800 Archive — A Health Record For Your Tesla
T800 treats your car’s telemetry the way a clinic treats medical history: the record follows your account, not the hardware. Every signal the T800 Box reads is encrypted and synced to our cloud as your vehicle’s permanent health record. If you sell the car, you choose what happens: transfer the Archive to the buyer, generate a Sell Report PDF, or delete everything.
The T800 Box in your garage keeps only a rolling ~30-day local buffer. That’s a cache, not an archive. The full multi-year record lives in the cloud — because that’s the only place it can realistically survive device swaps, disk failures, home moves, and the march of time.
Why the permanent record matters
- Resale premium. A verifiable multi-year T800 Sell Report is a real asset at sale time. Used-vehicle markets pay a documented 5–15% premium for cars with a complete, auditable history. “Here’s three years of daily cell voltage and suspension pressure” closes a deal that “Tesla said it’s fine” cannot.
- Retroactive analysis (the compounding benefit). Our CAN parsing gets smarter every month. When we ship a new monitor — a better bearing-wear detector, a more sensitive cell-imbalance catcher, a charging-profile anomaly model we haven’t built yet — we re-run it across your entire history. Your data from today becomes more valuable the longer it exists, and we tell you whenever a new monitor finds something retroactively. This is only possible because the raw data is still around.
- Cross-device history. Check your car’s full record from phone, web, or a friend’s laptop. Nothing is locked to a single piece of hardware in your garage.
- Survives everything. T800 Box swap, SSD failure, move, forgotten power plug — your vehicle’s history follows you.
- Open formats. Export the whole archive any time in parquet or CSV. Your data, your copy.
“Isn’t this a privacy trade-off?”
It would be — if the data contained personal information. It doesn’t. The Tesla CAN bus T800 listens to physically does not carry GPS, destination, route, cabin audio, camera feeds, or driver-behavior signals. Those are not on the bus we read. T800 Archive is pure engine/powertrain telemetry: voltages, currents, temperatures, pressures, SoC, motor state, and charging events.
We don’t have to make privacy promises about location data. Location data is physically absent from our pipeline. That’s why we felt comfortable making Archive the default — the data we store doesn’t tell anyone where you went, when, or why. It tells the story of how the car behaved, not the story of how you drove it.
Prefer strict local storage?
Open Strict Local Mode in your account settings and we’ll cap the record to the T800 Box’s 30-day local buffer. Daily reports still work. What you lose: multi-year history, retroactive analysis when new monitors ship, the Sell Report, and cross-device access beyond the buffer window. It’s a real trade-off — the full picture is in the Privacy Policy so you can decide with eyes open.
T800 Archive is included in the standard T800 subscription. No tier, no upsell, no extra line on your bill.
Data Privacy
T800 Archive stores raw CAN telemetry in our cloud by default, tied to your account. Because the CAN bus we read has no GPS, no location data, no cabin audio, and no identity information, there is nothing sensitive to upload — just the physical signals your car produces while it operates. If you want the archive capped to the T800 Box’s 30-day local buffer instead, Strict Local Mode gives you that control. See the Privacy Policy for exactly what is and is not stored.