Theory and operation
The most useful data forms a sequence: wake request, controller permission, contactor command, voltage response, READY state and delivered torque or charge.
Diagnostic Resources / Diagnostic guide
EV SCAN-DATA REFERENCE.
Organize useful PIDs by permission, energy flow, isolation, charging, propulsion and thermal function.
EV GUIDE20/24
Use this guide to organize evidence. Vehicle-specific high-voltage access, measurements and component isolation require OEM procedures, appropriate qualifications, rated PPE and approved test equipment.
GUIDE PURPOSE
Diagnose the system—not one isolated value.
Confirm vehicle state, operating conditions and the full DTC record before clearing evidence or opening the high-voltage system.
Diagnostic evidence
Build grouped lists for 12 V, pack/cells, contactors, isolation, charge limits, inverter/motor and temperatures rather than watching unrelated PIDs.
Safe diagnostic path
Record units, scaling, state conditions and timestamps, then graph related parameters on one time base.
Boundary and common error
A scan PID is controller-reported evidence—not direct proof of de-energization or conductor integrity.
Specifications, connector access, disable sequences, wait times and allowable tests vary by model and voltage architecture.