Wayne,

payload cannot cause bus errors.

2025-03-23 13:48:10.648 AEDT E (11528) esp32can: can1 stuck bus-off error state (errflags=0x00040cab) detected - resetting bus

OVMS# can can1 explain 0x00040cab
Bus error flags 0x00040cab:
| IR.2 Error-warning state
| SR.3 TX done | SR.2 TX buffer free
| ECC Stuff error in RX, segment data length code

If not by false timing, stuff errors can be caused by noise on the bus, some component flooding the bus with transmissions, or by hardware issues with the cabling.

Regarding Leaf CAN problems there ist a running investigation here: https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/issues/980

Adding the termination resistor would have been my next guess, but Richard already tried that, didn't help.

Are you absolutely sure the issue only (!) and reproducably (!) exists with that additional SOH poll entry?

Assuming that's the case: could it be this is a bus overload caused by the Leaf module itself when requesting all response frames without delay?

OvmsVehicleNissanLeaf::OvmsVehicleNissanLeaf()
…
PollSetResponseSeparationTime(0);

The framework default is 25 ms, so you could try commenting out that call.

Regards,
Michael

Am 24.03.25 um 07:48 schrieb Wayne Love:

Hi Michael,

Adding your patch did not make noticeable difference.

I noted that Leafspy pads the poll request with 0x00, whereas ovms pads with 0x55. I've also modified vehicle_poller_isotp.cpp to pad with 0x00 but again this made no difference.

Thanks

Wayne

On Mar 23, 2025, at 9:23 PM, Michael Balzer via OvmsDev <ovmsdev@lists.openvehicles.com> wrote:

Wayne,

do you currently apply my CAN timing patch? If not, please try that first.

Also, a general question to all Leaf developers: did anyone yet test fixing that random bytes write in `OvmsVehicleNissanLeaf::CommandWakeup()`?

Regards,

Michael

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