Front / Rear A/C control separation

[ldgregory]

Ok, I've searched around for the answer on this, read the manual a bazillion times, even took it to the BMW dealer (we'll get to that in a minute).

So here's the issue. I have tried every combination of settings in iDrive to gang and separate the front environment controls from the rear. No matter what configuration I have them in, my four year old can control the front A/C with the rear controls. It drives me bonkers when she accidentally hits one of the buttons with her foot, or deliberately changes them to make herself more comfortable. I would love that she could access her controls to change the heat/cold for the rear so she could make herself more comfortable, but she's more or less banned from touching the controls because it jacks us up in the front.

So, I take it to BMW to get a ski and snowboard rack installed. Drove back and had them remove it and refund the cost after driving 15 miles at 45MPH listening to that thing scream and whistle in the air. Sorry, got sidetracked.

Anyway. While I was there at BMW, I brought up the front/rear control issue. They had a couple people jump in and play with iDrive but couldn't get it figured out. Made an appointment for the next day to drop it off for them to look at. They kept it the entire day doing various things to it (like reflashing the computer), and ultimately, the next morning tell me. "It's supposed to work like that."

WHAT!?!?!?!? My last Dodge RAM truck allowed my kids to control the rear environment without jacking up the front. You're telling me my BMW can't do that?

So, I'm appealing to the folks here who know this most likely isn't the case. How do I keep the rear controls from controlling the front. I honestly don't even care if we can control the rear from the front anymore. I just want them independent of each other.

Any help will result in copious amounts of free virtual beer as thanks.

[ldgregory]

Ok, 38 views and no takers. Does everyone's work the way I've described it, or does yours work the way I'm expecting it to. It's easy to test. Turn on the AC and put the fan on level two or three, now reach behind you in the back and turn the fan all the way up and down to see if the front goes up and down too.

Note: The indicator in the front stays where it is. It's the forcefulness and amount of air coming out of the front vents that goes up and down with the rear controls.

[X5FX]

Not sure what you are saying, but here is how it works:

There are two menu settings in idrive, one says "enable rear controls" which allows the rear passenger to make climate adjustments independent of the front system when selected. When unchecked the rear system is turned off.

The second option says "use driver settings" when this is checked the rear system uses the same settings as the front.

The rear controls have zero effect on the front...it is not possible for the rear seat to control the front climate. Both fans are in the front dash though, so I think you are just confused by the sound of the rear system in the front dash.

I keep both options checked and dont let the kids use the buttons, because it overrides the second option.

[ldgregory]

Played with those settings in iDrive multiple times. Interesting to find out both fans are in the front dash, but the front does push more air when the rear fan is turned up higher. So not just noise, there is a greater volume of air coming out of the front. When I showed it to the people at BMW who first tried to show me I had the settings in iDrive wrong, they were perplexed as to why the rear controls increased and decreased air output in the front. They recommended bringing it in to have it serviced because it wasn't working right.

Service center says it works correctly. Do you think it's possible that whatever vent separator is used in the front dash for front fans and rear fans is not working and air from the rear fans is leaking into the front.

So just to be clear, it is not just an audible increase in the front, for each step up you set the fan in the rear, there is a corresponding increase in air force not only in the back, but in the vents in the front. This only happens if their fan settings go higher than our. i.e. we have our fans on say, two or three, and the kids go higher to four, five, six etc. If we have our fans at max, then they can play with theirs all day long and we don't feel a difference up front because we're at max.

One of the selling points for us was that it had front and rear climate controls which was the bomb in my Dodge pickup. When my kids turned up their fans in the rear, it didn't impact the amount of air coming our of our front vents.

[X5FX]

Then you have a problem.

The rear controls are not supposed to have any affect on the front other than when the rear air is on the front AC struggles to keep the front cabin cool on hot days. This is because BMW only uses one compressor for the front and rear instead of two sepearte systems. Therefor on hot days I keep the rear unit off unless I have passengers as the front stays much cooler.

I have never experienced greater airflow in the front due to the rear system being at a higher fan setting...if you are sure you have greater volume and not just greater noise then I would insist BMW fix the issue. If the dealer tells you the rear controls change the front system, then he is an idiot.

[ldgregory]

Thanks, that's what I needed to hear. When they told me "It's fine, that's how it's supposed to work", I was pretty floored. So we'll take it back in and have them figure it out.

Thank you.