Issues with hill start assist and cruise control after front-end damage

[Deleted member 43027]

Over a month ago now, my new 2023 Touring hatchback was sitting in a parking lot, when a tow truck driver cut a turn too close, tore into the front end, and pushed the car laterally:

I didn't even have plates yet. The collision center found no frame or suspension damage. The car is drivable again, but I'm still trying to complete repairs. The collision center and dealership have recalibrated the new bumper's radar sensors, but that hasn't corrected the subject of this post.

Here's my theory—the car now is biased towards thinking it's pointed downhill. This is what I've noticed in my testing:

• The manual transmission’s Hill Start Assist, in First, doesn’t work on slight uphill starts (car thinks it’s flat). In Reverse, it activates on flat ground (car thinks it’s pointed downhill).
• Both Adaptive Cruise Control and non-adaptive Cruise Mode, on flat ground (car thinks it’s going downhill), tap the brakes and/or cut throttle to stay well below the set cruising speed. Going uphill (car thinks it’s on level ground), they get closer to the set speed. ACC also generally follows too far behind traffic ahead.
• The steering's Lane Keep Assist System works fine. But if I understand correctly, it works entirely off the camera(s) above the windshield.
• (I know frequent complaints about ACC are common for many cars, including Hondas. But before this wreck, this Civic's system worked extremely well.)

Does anyone have any clue what parts should be inspected here? Maybe some kind of level sensor under the hood? I can't find anything searching for parts/guides online. We've already ruled out the front bumper's radar sensors. The car’s manual just says that the Hill Start Assist is related to the Vehicle Stability Assist / Electronic Stability Control system.

My guess is that something like a level sensor was knocked askew in the damage to the front end. This might get overlooked in a visual inspection. And in this case, the system would think it’s working fine, which would explain why it isn’t throwing a code or illuminating anything on the dash.

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[TypeRD]

I don’t know anything about it, but your theory makes a lot of sense based on your tests. Cars have so many sensors these days, I would not be surprised if some recalibration is needed after a wreck.