The vehicle is a network
Every modern vehicle runs on a distributed control network — gateway, ECUs, sensor nodes, failure domains. Diagnostics at DAC means reading that network at protocol level. Not reading a DTC list and guessing. The fault code is a symptom. The network tells you the cause.
DTCs are symptoms, not causes
A fault code tells you something logged an error. It does not tell you whether the ECU is faulty, the wiring is faulty, the power supply is faulty, or another module on the same bus is generating the condition. Treating the code as the cause produces wrong repairs.
What a DTC actually is
A stored event. It says: at some point, this monitor threshold was exceeded. It does not say why the threshold was exceeded, which component caused it, or whether it's still active.
What live data shows
Real-time values across all modules simultaneously. Injector pulse width, rail pressure, adaptation values, sensor outputs, commanded vs actual. The gap between commanded and actual is where the fault lives.
Network-level tracing
On a CAN/LIN network, one faulty node affects everything connected to it. A bad BCM can generate engine codes. A gateway routing fault can produce module-missing errors that aren't module failures at all.
Tools matched to platform
Generic OBD readers miss platform-specific data. Each manufacturer implements proprietary extensions, security gateways, and access methods that require platform-matched tooling to read correctly.
The diagnostic process
Every job starts with reading the network state before touching anything. No assumptions. No part-swapping based on codes alone.
SCAN Engine → DTC P0087 (fuel pressure low) SCAN TCU → No faults SCAN BCM → No faults SCAN Gateway → Online · routing OK LIVE Rail pressure (actual): 42 bar LIVE Rail pressure (req'd): 90 bar LIVE Pump duty cycle: 100% → Pump at max duty, pressure not building → Check: low-pressure circuit, strainer → NOT: injectors, rail sensor, ECU VERDICT Low-pressure supply fault ACTION Mechanical — not ECU work
What diagnostics covers
Engine & Fueling
Injection, rail pressure, lambda control, VVT, EGR, DPF/SCR. Live values across the full combustion and emissions management chain.
All supported platformsTransmission
TCU adaptation values, solenoid control, slip monitoring, clutch pack data. Auto and DSG/DCT where platform-supported.
Platform dependentChassis & Network
ABS, ESP, EPS, SRS module status. Bus health across CAN/LIN segments. Gateway routing faults. Module presence verification.
All supported platformsImmobiliser & Security
EWS / EIS / CAS / FEM / immo module status and handshake verification. Key adaptation state. Anti-theft DTC context.
See key programming pageCoding & Adaptation
Module variant coding verification, basic settings, adaptation resets and channel reads. Platform-specific blocks for VAG, BMW, Mercedes.
See ECU info pageBench & OBD-Dead
When OBD communication is absent: bench power, EEPROM access, and flash reads where supported. Applied when the vehicle can't be connected conventionally.
Case dependentMail-in module diagnostics
Some diagnostic work can be done on a bench without the vehicle present. If you're sending a module, give us the full context — the vehicle tells a story that the module alone doesn't.
Vehicle: Make / model / year / VIN Issue: Clear symptom description + when it happens Codes: Full DTC list — all modules, not just engine Modules: Part numbers + photos of labels History: Recent work, parts fitted, battery events, repairs