Log Error Catalog

• CAN0
• CAN1
• CAN2
• ACK error
• BIT0 error
• BIT1 error
• STUFF error
• FORM error

Occasional CAN bus ACK/BIT/STUFF/FORM errors are normal electrical noise on the vehicle network, especially at power-up or with an accessory attached.

Harmless in small counts. Only investigate if a single ride logs thousands, which can indicate a loose connector or a failing node.

• COV FAULT
• COV_FAULT

A cell reached the over-voltage protection threshold, usually at the very top of a charge or during regen on a full pack.

Occasional COV events near 100% are normal protection. Frequent COV faults on the same cell group suggest imbalance worth a balancing charge.

• Max allowed voltage difference
• voltage difference is

The spread between the highest and lowest cell exceeded the allowed limit, a sign of cell imbalance.

A wide spread at the top of charge is often transient. A persistent, growing spread across rides warrants a full balancing charge and monitoring.

• Read Attempts Failed
• PL536 Read
• Could not read PL536
• Reinitializing PL536

The BMS could not reliably read one of its cell-monitoring boards (PL/AFE). This is a communication problem between the pack controller and a cell group.

Sporadic retries can be normal. Sustained read failures on the same board can indicate a failing cell-board or harness and are worth a service check.

• CRC FAULT from PL
• Fault Status Reg
• Received FAULT from PL
• Received ALERT from PL
• Alert Status Reg

A cell-monitoring board reported a fault/alert register or CRC error over its internal bus.

Isolated events are usually transient noise. Recurring board faults point to a specific cell group and warrant inspection.

• invalid cell events
• INVALID/NO CELL TYPE

The BMS logged cell readings it flagged as invalid, often during initialization or a brief read glitch.

Generally benign self-diagnostics. Persistent floods can accompany a failing cell board.

• Chassis Isolation Event
• Chassis Isolation DANGER
• Low Chassis Isolation
• Chassis Isolation Fault
• MBB BMS Isolation Fault
• Isolation Fault

The bike detected reduced electrical isolation between the high-voltage system and chassis. It can be triggered by moisture or condensation, especially after washing or in high humidity. It is logged either as a bare fault flag or as a measurement: 'Chassis Isolation Event: N ohms to cell M', 'Low Chassis Isolation N KOhms to cell M', or 'Chassis Isolation DANGER!!' when the resistance collapses.

Often clears once the system dries out. A persistent isolation fault is a genuine HV safety concern. Have it inspected before riding in wet conditions.

• Cannot Connect Module
• MODULE_AWAITING_CONNECTION
• MODULE_INELIGIBLE

A battery module could not be brought online. The cause can be a voltage mismatch, a module controller issue, or (on multi-pack bikes) a pack that is out of range to join.

On swappable/multi-pack setups this can be expected when packs differ in charge. Repeated failures to connect the same module warrant service.

• Contactor Welded

The main board checks for voltage on the controller side of the main contactor while that contactor should be open, and writes 'Contactor Welded' when it finds some. The firmware files the line as INFO. A motor still turning, or a controller restarting while a charger connects, can put that voltage there for a moment. In one production log the line right after it reads the controller side at 131 V against a 115 V pack with the motor at 606 rpm: the motor generating, not a weld.

This log line is not the dash error 26 ('Contactor Welded Error'), which is the case to act on. A line on its own, with the bike powering on and off normally, is the check firing on a transient. If the dash shows error 26, the bike will not power down, or the line repeats at every key-off with the bike standing still, do not ride: have the contactor checked by a dealer.

• lack of precharge
• Did not close contactor
• ALL_CONTACTORS_OPEN

The main contactor did not close because the precharge voltage did not match: the controller bus did not reach the pack voltage before closing.

Occasional events on startup can be benign. Persistent precharge failures can indicate a contactor or precharge-circuit problem.

• CIB timeout
• Disabling CIB

The main board lost communication with an interface board within the timeout window.

Intermittent timeouts are usually transient. Repeated CIB disables can point to a wiring/connector issue.

• Internal Fault on BMS

The main board flagged an internal fault reported by a battery management system.

Note which BMS index is reporting and whether it recurs; recurring internal faults on one pack warrant service.

• State Machine Charge Fault

The BMS aborted or faulted the charge state machine, often because of a supply dropout, a handshake issue, or a protection trip during charging.

A one-off aborted charge is common with flaky supplies. Repeated charge faults on a known-good charger warrant investigation.

• Undervoltage fault

A charger reported low input/supply voltage, typically from a weak wall circuit, a long extension lead, or a shared circuit under load.

Usually an external-supply issue, not a bike fault. Try a dedicated outlet.

• Overcurrent fault

A charger tripped its own over-current protection and stopped delivering. Unlike undervoltage, this is not about the wall socket: the charger measured more current than it allows itself to deliver.

One trip that clears and does not come back is the protection doing its job. Trips that repeat on the same charger, on different outlets, point at the charger and are worth a dealer check.

• Too many Charge faults
• Shutting Down. Too many

The BMS shut the session down after repeated charge faults, as a protective stop.

A genuine protective shutdown. Stop using that charger and have the charging path inspected if it repeats.

• Voltage Critically High
• Critically High

A voltage exceeded the critical protection threshold.

A genuine over-voltage protection event. If it recurs outside the very top of charge, have the pack inspected.

• Hard Fault Exception
• Hard Fault

A controller firmware hard fault/exception: the processor hit an unrecoverable state and reset.

Note the firmware version and whether it recurs. Persistent hard faults warrant a firmware update or service.

• ABS SILA
• ABS light changed

The ABS module reported an error, often a wheel-speed-sensor signal issue. Gen1/Gen2 bikes log it as 'ABS SILA reporting an error'; native Gen3 (FST) bikes log the warning-lamp transition 'ABS light changed. Old: N New: N' instead.

If the ABS warning light is on, have the wheel-speed sensors and ABS module checked; braking still works without ABS but the safety feature is degraded.

• VIN Number Read Failed

The board could not read the stored VIN and reset it to uninitialized. This is a cosmetic/firmware bookkeeping event.

Harmless to operation. If the VIN shows blank in the app, a dealer can re-write it.

• Error log could not init

The BMS could not initialize its internal error log at startup. This is internal housekeeping.

Benign self-diagnostic; no rider action needed.

• ZeroBmsManagePackIo returned ZERO_RET_FAIL
• ZERO_RET_FAIL
• ZeroBmsManagePackIo
• ERROR: Zero

An internal BMS I/O management call returned a non-success code, usually a transient internal retry.

Benign in isolation; only relevant if paired with sustained pack faults.

• Entering Critical Error Shutdown
• Critical Error Shutdown

The firmware entered a protective shutdown after a critical error.

A genuine protective stop. Note what preceded it in the log and whether it recurs; a repeating critical shutdown warrants service.

• Failed To Fully Precharge

Before the main contactor closes, the motor controller's (Sevcon) capacitors are charged up towards the pack voltage. This record says they stopped short of it: the main board logs the capacitor voltage reached and restarts the controller to try again.

An occasional failed precharge that the restart clears is benign. Repeated failures on most key-ons, or a capacitor voltage that keeps falling, point at the precharge circuit, the contactor or the controller and are worth a dealer check.

• Restarting Sevcon
• cutout fault
• Sevcon

The motor controller (Sevcon) hit a cutout fault and was restarted to clear it. The cutout is often a transient torque/throttle or thermal protection trip.

An isolated cutout during hard acceleration can be normal protection. Frequent cutouts warrant a controller/throttle inspection.

• Current sensor calibration

The current sensor calibration was not set, so current readings may be less accurate until calibrated.

Benign for riding; a dealer tool can calibrate it if energy figures look off.

• Stats Read Failed
• resetting to
• Resetting All Stats

The BMS could not read stored statistics and reset them to defaults. This is internal housekeeping and occasionally follows a firmware update.

Benign; some lifetime counters may reset. No rider action needed.

• Quick Self Test Error
• Quick Self Test Failed

The BMS power-on quick self-test flagged a subsystem before going online, for example cell measurement ('Cells Failed') or the pack-I/O ADC ('PackIO ADC Failed').

An isolated self-test miss at boot can be transient. Repeated failures of the same subsystem point to a hardware issue on that pack and warrant service.

• SelfTest finished with warnings
• Self Test finished with warnings

The BMS completed its self-test but raised one or more non-fatal warning flags (a bitfield). These are recorded diagnostics, not a hard failure.

Benign if the bike operates normally. The flag value identifies which check was flagged for a technician if it recurs.

• Startup Failed with code

A BMS startup step failed and reported an error code; the controller typically retries the sequence.

Occasional startup retries that then succeed are usually benign. Persistent startup failures on one pack warrant service.

• Attempting to recover from Charge Fault
• recover from Charge Fault

After a charge fault the BMS is retrying to resume charging. This is a normal recovery step, not a hard stop.

Benign if charging then continues. If it pairs with repeated charge faults on a known-good charger, see the charge state-machine family.

• Accelerometer Selftest Failed
• Accelerometer Self Test Failed

The onboard accelerometer (used for tip-over / lean sensing) failed its power-on self-test and is retrying.

Usually clears on retry and is harmless. A sensor that never passes can disable tip-over detection, so it is worth a service check if it fails every boot.

• Module loopback lost

The main board lost the loopback/heartbeat with a battery module: a communication dropout between the MBB and that module.

Isolated events are transient. Repeated loss on the same module points to a connector or harness issue on that pack.

• Dtc set because of bms can
• DTC set because of bms can

The main board set a diagnostic trouble code because it hit a CAN communication error talking to a BMS.

Isolated events are transient noise. A persistent DTC from BMS CAN errors warrants checking the pack CAN wiring and connectors.

• command mode on RN-42
• RN-42 failed

The onboard Bluetooth module (RN-42) did not exit command mode and was reset via its reset pin. This is a benign comms retry.

Harmless; affects only the phone Bluetooth link, not riding or charging.

• Settings Read Failed
• Resetting All Settings to Defaults

Stored settings could not be read and were reset to defaults. This is internal housekeeping and sometimes follows a firmware update.

Benign; some saved preferences may revert. No rider action needed.

• watchdog timeout to
• allow bootloader time to start

The firmware extended the watchdog window so the bootloader has time to start. This is a normal part of the boot or firmware-update sequence.

Informational boot housekeeping; no rider action needed.

• WDT Timeout
• Watchdog Timeout
• Watchdog reset

A controller's watchdog timer expired and reset the processor because the firmware stopped servicing the watchdog (a hang or an overrun). A stack trace is logged.

An isolated watchdog reset that recovers is often transient. Repeated WDT timeouts point to a firmware issue and warrant a firmware update or service.

• BMS Disable -

The main board logged that the battery management system cut the pack off: 'Low Bat' when it ran out of usable charge, 'High Temp' or 'Low Temp' when the pack was outside the temperature range it will deliver power in. The record carries the pack voltage and remaining capacity (Low Bat) or the pack temperature (High/Low Temp), the module and its status flags.

A Low Bat disable at or near 0% after riding the pack flat is the protection doing its job: recharge before riding. A disable at a healthy state of charge, or a temperature disable in normal weather, is not expected and is worth a check of the pack and its sensors.

• Batt High Temp Stage
• Batt Low Temp

The main board logs the pack's temperature state as it changes: 'Batt High Temp Stage 1' and 'Stage 2' as the pack passes its high-temperature thresholds, 'Batt Low Temp' when it is too cold, and 'Batt Temp Okay' when it is back in range. Each record names the module and its temperature.

A first-stage high-temperature record after hard riding on a hot day is protection working; let the pack cool. Stage 2, or high-temperature stages in mild weather, deserve a check, as do low-temperature records at temperatures the bike normally rides in.

• Exceeded Max Charge Amps

The main board logs a battery module whose charging current stayed above its limit for a moment: the record names the module, by how many amps and for how many seconds the limit was exceeded, and the current when it was logged (charging current is negative in this log).

Isolated records while charging, especially from a fast or supplemental charger, are the board noting a brief overshoot. Many per charge on the same module are worth raising with a dealer.

• High Mot/Ctrl

The main board logs the motor and controller temperatures (in °C) when they run high. In the logs we have read, it appears from about 75 °C at the motor.

Expected after sustained high speed, long climbs or hot weather. Frequent records on gentle rides or cool days, or motor temperatures well past 100 °C, point at airflow or cooling and are worth a check.

• BMS Long Term Storage Stats

While the bike is stored, the BMS writes a periodic record of its lowest and highest cell voltage, the balance between them, its own temperature and how many balancing resistors are active. In the logs we have read, it writes one every twelve hours.

Informational: a storage diary, not a fault. A balance that grows from record to record, or cell voltages falling steadily, is worth watching; follow the owner's manual on the charge level to store at.

• Fault pending
• Fault cleared
• Fault set

The firmware logs a generic fault lifecycle: a named fault became active (set), was counting down (pending), or resolved (cleared). Severity depends on the named fault.

A cleared fault that does not return is resolved. Look at the specific fault name and whether it stays set.