Vehicle Wake, Sleep, Accessory, And Retained-Power States
Canonical definition: Vehicle wake and sleep behavior is the coordinated transition of power rails, network transceivers, gateways, modules, audio sources, DSPs, amplifiers, retained-accessory functions, user controls, and protection states.
Build The State Matrix
| State | Required audio and network record |
|---|---|
| vehicle off / standby | parked current, transceiver state, stored preset, wake sources |
| accessory / retained accessory | source availability, user controls, amplifier state, timeout |
| run | normal source, charging, network, DSP, amplifier, and retained functions |
| crank / stop-start / brownout | voltage, reset, mute, output, communication, restored state |
| shutdown | amplifier disable, output mute, state save, interface and network sleep |
| wake | source of wake, modules awakened, boot order, audio enable, user state |
| fault / update / disconnect | safe default, logging, bypass, recovery, service access |
Audio Enable Sequence
power stable
→ controller and DSP reset / self-boot
→ verify project and communication
→ load or confirm protected preset
→ keep outputs muted
→ enable amplifier remote
→ confirm amplifier ready
→ slew audio to approved level
Shutdown reverses the risk: slew or mute audio first, disable amplifiers, preserve required state, then allow the controller, transceiver, and network to sleep.
Wake Sources Are System Inputs
- key or accessory signal
- door, lock, retained-accessory, or body-network activity
- CAN or LIN wake pattern
- audio or DC-offset sensing
- phone, Bluetooth, USB, charger, diagnostic, or update connection
- local button, timer, or controller watchdog
Each wake source needs an owner, allowed states, timeout, failure behavior, and parked-current result.
Parked-Current Measurement
- Configure the vehicle, keys, doors, locks, chargers, phone, and test equipment.
- Measure from key-off through the complete delayed-sleep period.
- Avoid opening doors, polling modules, or reading instruments in ways that restart the timer.
- Record step changes and identify which interface or module owns each one.
- Repeat after reconnect, fault, update, and normal user operation.
Common Back-Power Paths
- USB programmer or laptop ground
- signal cable between separately powered devices
- microcontroller GPIO into an unpowered DSP or transceiver
- remote-turn-on wiring
- diagnostic adapter
- unpowered network transceiver that is not passive on the bus
Release requires measured final sleep, stable parked current, correct wake behavior, protected crank and brownout handling, and reliable restoration of the approved source and preset state.