I'm getting an ACC failure while hauling a motorcycle on a hitch trailer. I'm assuming the weight (250lbs) may be doing something to offset the camera balance.
I also use the accersory outlet to run the trailer lights.
Anyone else losing ACC while towing?

 

Do you have air suspension that would maintain a level profile?

 

Me, and other friends, get ACC failures randomnly, and maybe true that it may happen more often during towing. The inconvenience is that you lose your the cruise control feature and other features.

Most of the time it goes away after a restart, but if you are on the highway on a long trip, it is very inconvenient..

I have air suspension..

 

No, standard suspension.

 

I could believe the squat causing an ACC fault.

 

Tongue weight should not have that much of an impact. What about towing 7k pounds with 15% on the tongue?

Has anyone had a dealer recalibrate ACC with the hitch loaded? Maybe just a general software update?

 

Porsche ACC is glitchy (to say the least.) If ACC camera lens doesn't "see" traffic for few minutes, ACC faults out. Why so is a million dollar question.

In your case, with additional tow weight, your ACC camera lens might be pointing "north" (vs horizontal) thus faulting out.

ACC faulting out is irritating (First World problem) because normal cruise is simultaneously also deactivated.

 

And when the hitch is not loaded?

 

What an excellent idea to obscure the license plate (to avoid speed cameras)

 

Your ACC is affected by the altered stance (squatting) caused by the hitch load. Others have posted the same problem while towing. Read all about it in this thread:

https://rennlist.com/forums/cayenne-...ntrol-acc.html

One of my posts in that thread: Your dealer can perform a special ACC calibration for towing. See excerpt from a Service Bulletin published September 2021.

Condition
The customer reports a warning in the instrument cluster that tells the driver that ACC is not available. The workshop confirms this condition and finds fault code C110300. This failure mode indicates vertical alignment calibration has failed.

Technical Background
This condition is exacerbated by a heavy load in the vehicle’s cabin and by towing. Additionally, after an alignment, the vehicle may also fail its calibration.
Porsche plans for a permanent solution to this condition in future software. Until this software is available, please use the following recommendations.

It goes on to describe the modified calibration procedure which adds extra weight in the cargo compartment to squat the rear end during calibration.

See attached TSB.

 

Towing is a great reason to buy the self leveling air suspension system. I had it in my 2006 CS and towed a 6,000 lb Airstream. Although there was no ACC back in the day, my Cayenne self leveled every time I hitched it up. Vary happy with it!

 

I have a 2022 Cayenne Platinum S with towing package; on a recent trip from midwest to East coast had the same problem both ways. on the outbound I had the no trailer but a packed rear and the ACC became inactive after about 100 miles. on arriving in NY I set up an appt with dealer but it seemed to reset after a week. on the trip back I had a 8x10 U-Haul trailer with maybe 1000 lbs max (car rated at 7000 lbs) and the same thing happened. Not having ACC or cruise control on a 15 hr drive is HIGHLY inconvenient . Again set up an appt with dealer in Chicago western suburbs but by the time the appt came it had reset. However they kept it a week and basically said its a 'known issue' and there is a bulletin out (see below in this thread); they were very understanding and recalibrated with some weights in the back but no guarantees of a permanent fix. I must say they were as helpful as they could be. Apparently the car has steel suspension that does not 'reset' itself quickly; no guarantees that an air suspension would solve this either.

It seems like Porsche has know about this issue for a while (bulletin dated 2021) but yet they have continued selling cars. I will continue driving but need to inform Porsche that this is unacceptable on a $112K automobile!

 

I bought my Porsche Cayenne S in Florida, and the first day while driving to Houston, I had the ACC fail and with that cruise control was disabled most of the trip. Later, after several viisits to thecdealer, the frequency of the problem was reduced, but never fixed.

I have air suspension, and it doesn't matter if I am towing or not.. Sometimes the error disables the stability system, which really concerns me when driving on the highway and is storming around..

I have taken my Porsche to the dealer since I bought it in 2019, and they were never able to fix it..

Most of the time, they state that they could not reproduce it, since it happens randomly and resets by itself, so I have to live with it as many owners do too.. Seems like those system errors do not save any meaningful troubleshoot information or the dealer just don't care about fixing it..

Same as some other random electronic bugs that come sporadically and go away..

One thing that I have noticed is that Porsche electronics hardware, GPS, and programmers suck a lot more compared to other brands..

 

And you think Porsche cares? My Cayenne, after strike three, they offered a buyback. At a generous $20K less than market value.

Remember Porsche (VW) is the same company that created, funded and made operational a separate engineering division for emissions defeats.

 

They can't. It is ROM coded. Maybe a software updates can supersede. But Porsche does not want invest in this...they already have your money. A few dealer service reimbursements and even less low balled buybacks is calculated into the profit equation. It is all about profits.