`canair dtc`¶

usage: canair dtc [-h] [--all] [--history] [--no-log] [--no-retry]
                  [--label LABEL] [--state STATES] [--mask HEX]
                  [--protocol {auto,uds,kwp}] [--clear] [--group HEX] [--yes]
                  [--session] [--wake] [--wican WICAN]
                  [--transport {slcan-tcp,wican-ws,elm327-tcp}]
                  [--no-fallback] [--wait] [--elm-timeout MS]
                  [--timeout SECONDS] [--json] [--verbose] [--timings]
                  [--reboot] [--unsafe] [--force]
                  [ECU]

[UDS] Read stored Diagnostic Trouble Codes with UDS 0x19 (reportDTCByStatusMask), or clear them with UDS 0x14. Clearing mutates ECU fault memory and prompts for confirmation unless --yes is given.

positional arguments:
  ECU                   ECU name or TX ID (e.g. BMS or 7E4)

options:
  -h, --help            show this help message and exit
  --all                 Scan every ECU in the profile for DTCs (protocol auto-
                        selected per ECU)
  --history             Show the most recent logged scan from dtc_log.yaml
                        without touching the device (useful when the WiCAN is
                        offline). Decodes each code and reports the change
                        since the previous scan. Scope is --all by default, or
                        a single ECU when one is named.
  --no-log              Don't record this scan to the profile's dtc_log.yaml
                        (scans are logged by default, reporting what
                        cleared/appeared since the last scan)
  --no-retry            With --all, don't retry unresponsive ECUs (by default
                        a no-response ECU is retried once with a wake + longer
                        timeout so it isn't skipped)
  --label LABEL         Optional label for the logged scan entry (e.g. 'before
                        clearing')
  --state STATES, --vehicle-states STATES
                        Vehicle power state(s) during the scan, recorded on
                        the log entry (comma-separated, e.g. 'READY' or
                        'SLEEP, PLUGGED'; case-insensitive). Vocabulary from
                        vehicle_states.yaml (`canair states`).
  --mask HEX            statusOfDTC mask for the UDS read (hex, default FF =
                        all; falls back to 08 if the ECU rejects FF with
                        requestOutOfRange)
  --protocol {auto,uds,kwp}
                        DTC protocol: uds (0x19/0x14), kwp (KWP2000
                        0x18/0x14), or auto (from the profile's id_protocol).
                        Default: auto
  --clear               Clear DTCs (ClearDiagnosticInformation 0x14) instead
                        of reading
  --group HEX           groupOfDTC to clear (3-byte hex, default FFFFFF = all
                        groups)
  --yes, -y             Skip the clear confirmation prompt
  --session             Enter extended session (10 03)
  --wake                Wake ECU from deep sleep (10 01)
  --wican WICAN         WiCAN address: ap or IP (default: config
                        transport.host / default_wican=ap)
  --transport {slcan-tcp,wican-ws,elm327-tcp}
                        CAN transport: slcan-tcp (raw CAN), wican-ws (WiCAN
                        ELM327 WebSocket), or elm327-tcp (direct ELM327
                        adapter over TCP). Overrides the config
                        `transport.type` (default: slcan-tcp).
  --no-fallback         Don't auto-fall-back to other configured devices when
                        the selected one is unreachable (see config
                        transport.fallback).
  --wait                Keep retrying to reach the device indefinitely, then
                        start as soon as it comes online (Ctrl-C to stop). For
                        'monitor', also reconnects forever if the connection
                        drops mid-session (auto-failover to another same-
                        transport device is bounded by default; --wait makes
                        it unbounded).
  --elm-timeout MS      ELM327 ECU response timeout in ms (sent as ATSTxx
                        after init)
  --timeout SECONDS     Overall UDS response timeout in seconds (default 3.0
                        ELM / 2.0 raw). Overrides any per-ECU
                        response_timeout_ms for the whole run.
  --json                Output results as JSON
  --verbose, -v         Show raw transport traffic and expressions
  --timings             Print per-ECU/PID round-trip timing stats on exit (to
                        stderr)
  --reboot              Reboot WiCAN after session to restore AutoPID mode
  --unsafe              Bypass dangerous command blocklist (requires explicit
                        per-command consent)
  --force               Ask a session already holding the connection to
                        release it, then wait for it

examples:
  canair dtc BMS                       Read all stored DTCs (status mask FF)
  canair dtc --all                     Scan every ECU (logs + shows changes since last scan)
  canair dtc --all --no-log            Scan every ECU without recording to the history log
  canair dtc BMS --label fixed         Read + log a single-ECU scan with a label
  canair dtc --all --state ready       Log a full scan tagged with the vehicle state
  canair dtc BMS --mask 08             Read confirmed DTCs only (mask 0x08)
  canair dtc IGPM --session --wake     Wake + read in extended session
  canair dtc BMS --json                Machine-readable output
  canair dtc BMS --clear               Clear all DTCs (asks to confirm)
  canair dtc BMS --clear --yes         Clear without the confirmation prompt
  canair dtc BMS --protocol kwp        Force KWP2000 readDTCByStatus (0x18)
  canair dtc --history                 Show the last logged full-sweep scan (offline, no device)
  canair dtc BMS --history             Show the last logged scan for one ECU (offline)
canair dtc¶

`canair dtc`¶
