commaai
VW MQB: Alpha Long faulting cruise control when feathering throttle.
Description:
With Alpha Long enabled, and disengage on throttle turned off, feathering the throttle, or going on and off throttle rapidly/repeatedly, will occasionally cause a cruise control fault. OP disengages "silently". There is no warning on the screen or notice to take over, other than the disengage sound, followed about a message about a cruise fault, and to restart the car.
Car: 2019 Golf R, Manual
OP version: nightly-dev 54cae2a
Route: 60cd64977874cb65/000000dd--df1550b5ed/24 (Right at the end of segment 24)
One thing to note, I'd have expected some more aggressive alert to go on, other than just a simple disengage when something like this happens. It's fairly "silent". I don't know if this is intentional or not, but I would have expected a more aggressive warning for something like this.
In case it helps, here's the route right after "rebooting" the car: 60cd64977874cb65/000000de--63b814f44a/0
vrabetz on discord mentioned this may be a dupilcate of #2766
after looking at the provided route, this is not the issue, all signals from opLong required are present on tx bus 128, and are not present on any safety rejection bus.
what happened here it seems is openpilot longitudinal control commanded accel without cruiseState being active, only enabled, when ECM sees this it permanently faults for the drive cycle which is what happened here, the accel signal goes to the inactive value for a few frames and then back to active, and ECM drops cruiseState and never re-enters, but opLong cruiseState never leaves active (before the fault), so this could also be a ECM re-entry minimum time limit.