Dual Zone Climate Control doesn't stay in sync

[RockJGC]

Does anyone else have a climate control that won't keep both zones in sync? At least a few times a week, I adjust the temp on the driver's side and notice that the passenger side isn't also changing. So I go into MMI, set the temperature to sync and it's fine for a day or two, then it goes out of sync and I have to do it over again and again....

Is it just my car?

[Neil F]

Not sure where in the MMI a setting is but press and hold the drivers button and the passenger side should be set to sync

[hahnmgh63]

Never had mine go out of Sync, S5, RS5, Q5. Are you sure someone isn't messing with the passenger side knob. Once you touch the passenger side know it kicks it out of sync. Only controls Synced up with the Drivers side. If all there is good then maybe something available with Vagcom under Long Coding?

[Smac770]

You'd have to better document the moment of sync loss. Is it sync'd on engine off and then not sync'd on next engine on, is it dropping sync while engine on; when you notice it, is the passenger temp different (before you turn the driver's temp).

The only visual on sync status is if you press the temp knob and it brings up the temp dial display, you see at the bottom center symbols for the two functions in the CAR - A/C menu: auto recirculate and sync. Or check the status in CAR - A/C menu. The only two ways to break the sync is to select off via the CAR - A/C menu or to change the temp using the passenger side knob.

Maybe your passenger side knob is developing a glitch.

[carrrnuttt]

Do you have a second key?

If I use my spare set of keys it un-syncs my system since I never set sync under that key. Not sure if it does it on start or unlock (after it recognizes the key).

[RockJGC]

You'd have to better document the moment of sync loss. Is it sync'd on engine off and then not sync'd on next engine on, is it dropping sync while engine on; when you notice it, is the passenger temp different (before you turn the driver's temp).

The only visual on sync status is if you press the temp knob and it brings up the temp dial display, you see at the bottom center symbols for the two functions in the CAR - A/C menu: auto recirculate and sync. Or check the status in CAR - A/C menu. The only two ways to break the sync is to select off via the CAR - A/C menu or to change the temp using the passenger side knob.

Maybe your passenger side knob is developing a glitch.

So what happens is this----if I have climate set to 70 on both sides and synced, I can turn the driver's side knob up and/or down all day long and the passenger side always follows. But let's say I leave it at 70 and go home. The next day when I'm leaving, both sides are at 70 just as I left them, but when I turn the driver's side temp, the passenger side doesn't change. And then I go into the MMI system and it shows that it's not in sync, so I manually put it back into sync again. This happens sometimes, not every time. It seems completely random and I never know when it will go out of sync, but it definitely will not stay synced for more than a few days at at time.

And for everyone else, nobody is messing with the passenger side knob because this has happened many times when nobody was in the car except me. And yes, I'm using the same key all the time.

It's bizarre.

[RockJGC]

Not sure where in the MMI a setting is but press and hold the drivers button and the passenger side should be set to sync

Hmm....didn't know that. I've have to give that a try. I always go into the MMI menu to set it to sync.

[Smac770]

That is very odd. I don't know if there's a setting somewhere (J255 coding/adaptation/basic setting) that defines if sync should always set, not set, or retain previous on ignition. But that should be consistently every time, not every few days.

Best guess is your climate control panel is flaking out and it thinks its sensing action on the passenger knob. But this should be seen as a differing passenger temp. You should call the dealership and ask the service department if there are known cases on the B8 platform of sync unsetting without cause. Intermittent issues are the worst. Pressing the passenger button to bring up the temp UI will not break sync; only if there's a turning to change the passenger side temp.

I mean, it could be a random failure of the hardware that stores that parameter in EEPROM, but that's a stretch. May or may not be a cheap test depending on what you can find. Part is 8K1 820 043, and then revision BA (previously AC then AH) for no heated seats, BB (previously AD then AJ) for heated seats, or BC (previously AE then AK) for heated and cooled seats.

[hahnmgh63]

After that I'm thinking a long coding setting for the climate control, battery is weak, or climate control panel. Only you would know how old your battery is, you can check it if you have VCDS for aging. VCDS can also check the settings in the Long coding and see if there is one for the climate control sync or in the Hidden Green menu.

[Wantboost]

How about setting the sync and then saving the fob/seat in memory on the driver side door. ??

Sent from my SM-G975W using Audizine Forum mobile app