A single Linux daemon that reads live EV telemetry (battery, odometer, tire pressure, temperatures) and forwards it to a local REST consumer — designed for aa-proxy-rs for Android Auto EV routing and dashboards. One binary serves three adapter families, selected at runtime by the config file:

Heritage: aa-proxy-obd was previously known as canze-rs and forked from manio/canze-rs — the original Renault Zoe SOC logger, whose full Zoe support (TPMS, odometer, energy) lives on as the zoe profile. The name is a tribute to the CanZE project, which remains the reference for the underlying PIDs. Its home is aa-proxy/aa-proxy-obd.

Adding a new vehicle requires no Rust changes — see Vehicle profiles.

WiCAN Pro users get whatever their AutoPid configuration exposes (typically SOC plus outdoor temperature); the WiCAN firmware decodes PIDs itself, so the daemon does not load a profiles/ file for device.type = "wican".

While the adapter is reachable and the car is awake, the daemon polls and POSTs JSON to three endpoints on localhost. For each endpoint, it sends only if at least one relevant field was produced this cycle (absent fields are omitted); otherwise the endpoint is silently skipped.

If the active profile reports SOC as a percentage and battery_capacity_wh is set in config, the daemon derives battery_level_wh = SOC × capacity / 100 automatically when the profile doesn't report Wh directly.

aa-proxy-obd [OPTIONS] [COMMAND]

Commands:
  pair    Pair the configured Bluetooth/WiCAN device (and optionally save the passkey)

Options:
  -c, --config <CONFIG>    Config file path [default: /etc/aa-proxy-obd.toml]
  -d, --debug              Override the configured log level to debug
  -h, --help               Print help
  -V, --version            Print version

Only device.type, the device's address (bt_mac for bluetooth/wican, usb_port for usb), and vehicle.profile (for the ELM327 types) are required. Everything else is optional and falls back to the defaults shown below, so a minimal config is just:

[device]
type   = "bluetooth"
bt_mac = "AA:BB:CC:DD:EE:FF"

[vehicle]
profile = "ev6"

Full set of options with their defaults:

[device]
type                      = "bluetooth"                # bluetooth | usb | wican

bt_mac                    = "AA:BB:CC:DD:EE:FF"        # bluetooth + wican; the adapter's MAC
bt_passkey                = 1234                       # optional; enables in-process pairing
bt_max_connect_retries    = 5                          # bluetooth + wican
bt_timeout_secs           = 10                         # bluetooth + wican; per-attempt connect/response timeout

usb_port                  = "/dev/ttyUSB0"             # ls -l /dev/ttyUSB* /dev/ttyACM* 2>/dev/null
usb_baud                  = 115200

[vehicle]
profile                   = "ev6"                      # ignored when device.type = "wican"
battery_capacity_wh       = 77400                      # optional; enables derived battery_level_wh

[daemon]
poll_interval_secs        = 10
car_sleep_interval_secs   = 100                        # poll interval while the car is asleep
log_level                 = "info"                     # off | error | warn | info | debug | trace
log_file                  = "/var/log/aa-proxy-obd.log"
api_base_url              = "http://localhost"
bridge_dropouts           = true
publish_failure_threshold = 5
publish_breaker_secs      = 300
cycle_failure_limit       = 20

The wican device type connects over Bluetooth, so it shares the bt_* options (bt_mac, bt_passkey, bt_max_connect_retries, bt_timeout_secs). Keys under [device] that don't apply to the selected type are ignored.

Profile JSON files ship under profiles/. At install time, copy them to /etc/aa-proxy-obd/<profile>.json (e.g. profiles/ev6.json → /etc/aa-proxy-obd/ev6.json). A profile lists one or more sources, each with a kind discriminator.

{
  "kind": "uds_pid",
  "ecu_tx": "7E4",          // request header
  "ecu_rx": "7EC",          // response filter
  "pid": "220105",          // service + PID (UDS / Mode 22 typical)
  "pre_request": "10C0",    // optional; sent before the PID, errors ignored
  "multiframe": false,       // opt-in to ISO-TP flow-control reassembly
  "fields": [ /* FieldSpec */ ]
}

{
  "kind": "broadcast",
  "init": ["ATCRA", "ATH1", "ATS1"],
  "command": "ATMA",
  "deadline_ms": 6000,
  "idle_timeout_ms": 600,
  "stop_when": ["external_temp_celsius"],   // field names that end the scan early
  "frames": [
    { "can_id": "673", "fields": [ /* FieldSpec */ ] }
  ]
}

• Battery: battery_level_percentage, battery_level_wh, external_temp_celsius, battery_state_of_health, battery_voltage, battery_current, interior_temp_celsius
• Odometer: odometer_km, trip_km
• Tire pressure: tire_fl_kpa, tire_fr_kpa, tire_rl_kpa, tire_rr_kpa

1. Identify the OBD ECU TX/RX headers and the PID(s) for the parameters you want. CanZE is an excellent reference.
2. Work out each field's byte (or bit) offset, length, multiplier, and offset within the response payload.
3. Drop a new JSON file under profiles/ (and copy it to /etc/aa-proxy-obd/<name>.json).
4. Point profile = <name> at it in the config. No code changes required.

If [device].bt_passkey is set, the daemon registers a BlueZ agent at connect time that supplies the passkey during first pairing (this applies to both the bluetooth and wican device types). BlueZ ignores the agent for already-paired devices.

For one-shot setup:

aa-proxy-obd pair --passkey 1234     # or omit --passkey to be prompted

The subcommand discovers the device (if not already known to BlueZ), pairs it, and on success offers to write the passkey back into the config under the appropriate [device] key. Config comments and formatting are preserved.

• Per-endpoint circuit breaker. After publish_failure_threshold consecutive POST failures on an endpoint (default 5), the daemon stops POSTing there for publish_breaker_secs (default 300s), then probes once and closes on success.
• bridge_dropouts. When enabled (default), if a cycle produces no payload for an endpoint but the previous one did, the daemon re-POSTs the last-good value so downstream sees continuity. The cache clears when the car sleeps.
• Cycle health watchdog. If cycle_failure_limit consecutive cycles produce zero successful POSTs (excluding intentional sleep cycles), the daemon logs an error and exits code 2 for a supervisor to act on.

cargo build --release

The vendored .cargo/config.toml defaults the target to aarch64-unknown-linux-gnu so the release build cross-compiles for common SBCs (e.g. Radxa Zero 3W running an aa-proxy-rs image). Run the test suite on the host with cargo test --target <host-triple>.

GPL-2.0. See LICENSE.

• Original manio/canze-rs by Mariusz Białończyk — the Renault Zoe SOC logger and TPMS/multiframe work this fork builds on.
• The CanZE project — primary reference for OBD PIDs.
• Reference projects whose capabilities this daemon absorbs: aa-proxy-go-obd-feeder (USB OBD) and aa-proxy-wican (WiCAN Pro).