[AndreyT]

Originally Posted by ENINTY

So this is not correct. In auto mode the AC indicator lights, but it only means the AC compressor is "available" to be used to condition the air; it doesn't mean the AC is running constantly.

No. AC is either always activated or never activated, which is indicated by the AC light. The CC system will never activate or deactivate AC by itself. This always requires manual action. Basically, the AC control in 3 series is no different from some '80s Buick: you can turn it on manually, or you can turn it off manually. That's it.

Meanwhile, "Auto" mode has nothing to do with AC or temperature. "Auto" mode only controls fans (speed and airflow distribution) and nothing else.

[ENINTY]

Originally Posted by AndreyT

No. AC is either always activated or never activated, which is indicated by the AC light. The CC system will never activate or deactivate AC by itself. This always requires manual action. Basically, the AC control in 3 series is no different from some '80s Buick: you can turn it on manually, or you can turn it off manually. That's it.

Meanwhile, "Auto" mode has nothing to do with AC or temperature. "Auto" mode only controls fans (speed and airflow distribution) and nothing else.

Well not really. If the AC compressor would be working at for a longer period than a few minutes, say 33 deg. F, the evaporator would freeze over. The light means the AC will activate when the system requires it to. The AC needs to be active for the temperature wheel on the dash to provide cool air to the dash vents. When the light is off (which you can do in auto mode) the AC will not activate and the system will not work correctly in auto mode. I asked this question to my SA in 2006 and he brought out the BMW E90 tech manual (that the mechanics are trained with) where I read how the system operates.

[ENINTY]

Originally Posted by DUI Elite

This is not correct. AC Indicator light indicates that AC cycling is ON.

The second half of your statement is true for any car. The compressor isn't always engaged. The clutch for the belt on the compressor engages (and disengages) every few minutes.

Agree with the second part.

[AndreyT]

Originally Posted by ENINTY

Well not really. If the AC compressor would be working at for a longer period than a few minutes, say 33 deg. F, the evaporator would freeze over.

When I say that "AC is activated", I do not mean that the AC compressor is running non-stop. As clearly stated above, what I mean is that AC is "turned on" the way it is turned on in any other car. Once it is turned on, it will operate in typical "continuous" AC mode, which for AC means that the compressor clutch gets periodically engaged and disengaged to ensure proper operation of the compressor and evaporator without anything freezing over.

Originally Posted by ENINTY

The light means the AC will activate when the system requires it to. The AC needs to be active for the temperature wheel on the dash to provide cool air to the dash vents. When the light is off (which you can do in auto mode) the AC will not activate and the system will not work correctly in auto mode. I asked this question to my SA in 2006 and he brought out the BMW E90 tech manual (that the mechanics are trained with) where I read how the system operates.

No. It is not correct to say that the system will "activate when the system requires it to for air cooling", regardless of what the SA told you. (Apparently, you and/or him misunderstood something in that manual).

The purpose of AC unit is not even remotely limited to cooling the air. The purpose of AC unit is to cool and dehumidify the interior air. For this reason, when you enable AC (regardless of Auto or Manual mode) it will run continuously (as I described above) even if cooling is totally unnecessary for achieving the requested target temperature. For example, if you ask the CC system to warm up the interior air with the AC still enabled (the green light lit up), the CC system will continue to run the AC. In this case the AC will cool and dehumidify the air, and then the heater will reheat the air again to the requested temperature. The CC system in this case knows that the AC is not needed for cooling, yet it assumes that you enabled the AC unit specifically to dehumidify the air.

This is actually pretty easy to verify in practice. Start the car and let it idle with AC off. Crank the temperature control to full heat, all the way up. Now activate the AC by pressing the snowflake button. According to what you said, the AC should not engage, since "it is not required" in this case. However, in reality it will engage immediately in 100% of cases, which is easily felt and heard when the car is idling.

In fact, there's currently no car [I know of] on the market that can activate/deactivate the AC automatically, on request of CC system. All CC systems in every car I saw work the same way with regard to AC: you can only disable or enable the AC manually. You turn it off - it stays off. You turn it on - it runs all the time. I don't know the exact rationale behind this. It might be something safety or fuel-economy related, I guess...

Again, "Auto" mode has nothing to do with controlling the temperature and/or AC. "Auto" mode controls only the fan speed and air stream distribution between the three levels. So, it is really "Auto Fan" mode and nothing else. This is why "Auto" mode can be enabled/disabled indirectly through the three air distribution buttons on the left end of CC control panel.

[John 070]

Learned something today, when you're on cruise and you step on the clutch, the cruise reengages when you let off the clutch. On my Nissan the clutch disengages cruise altogether.

[AndreyT]

Originally Posted by John 070

Learned something today, when you're on cruise and you step on the clutch, the cruise reengages when you let off the clutch. On my Nissan the clutch disengages cruise altogether.

It only works when you do it relatively quickly (as for a shift). There's a specific time limit. If you push the clutch pedal and hold it longer than that limit, the cruise will disengage.

[AndreyT]

Originally Posted by Rhodes7586

When you've turned your wipers on and then stop the vehicle in traffic, the wipers stop as well.

They actually just slow down. And with auto-sensing wipers it will depend on how much water there is on your windshield, not on the car speed.

Originally Posted by Rhodes7586

The owners manual says to never lock someone inside the car using the fob (while you are outside of the car) because then they can't get out. Not True, If you push the unlock button on the dash twice, you can then pull the inside handle and open the door.

Is this really different from simply pulling the inside handle twice and opening the door?

Originally Posted by Rhodes7586

throw your keys into the trunk then close it, it will magically open again. Safety feature that makes it impossible to lock your keys in the trunk

Must be a part of Comfort Access...

Originally Posted by Rhodes7586

-having the clutch depressed at a stop is actually burning up the clutch (clutch plates never release from each other completely, there is always a bit of friction between them)

I don't think this is accurate.

Originally Posted by Rhodes7586

If you need to look at the mileometer or trip meter after you've switched off, you can simply press the trip reset button in the instrument cluster and it will switch on the OBD.

Well, you can also press the clock button on the radio to check the current time. This doesn't just power up the radio, this seems to power up the entire car (i.e. power seats start working again and everything else)

Originally Posted by Rhodes7586

lift the spare tire compartment cover up all the way to the roof of the trunk...it will click and lock in place to stay up.

Coupe only?

Originally Posted by Rhodes7586

when you use cruise control when the headlights are on a little marker slides around the speedometer to the speed you have set

"Headlights are on"? No, there's no need for headlights. When the cruise is active, the little marker is always there, perfectly visible regardless of headlights. Turning on headlights only makes it backlit, just like the rest of the cluster.

Originally Posted by Rhodes7586

While the CD is playing, press on the on the button under "LIST" and you will get all your track names instead of track number.

What you will get will depend on the type of disc you have in the player. If you have an ordinary basic Audio CD in there, there's no chance to see the track names - the radio does not know the track names, which is why it can't possibly display them. (Enhanced Audio CD formats can supply this information though).

MP3 CDs display file names (not track numbers) in "normal" mode as well as in list mode, i.e there's no difference.

There's also the third mode: INFO mode, in which the radio displays the song and album name retrieved from the MP3 tags stored inside the MP3 file.

Originally Posted by Rhodes7586

did you guys now about the overdrive feature , the is a button behind the pedal.

This is, like, a well-known feature of virtually all automatic-transmission cars. I'd be surprised to find out that in this age they still implement it with something as primitive as a plain button behind the pedal. Do they?

[ENINTY]

Originally Posted by AndreyT

When I say that "AC is activated", I do not mean that the AC compressor is running non-stop. As clearly stated above, what I mean is that AC is "turned on" the way it is turned on in any other car. Once it is turned on, it will operate in typical "continuous" AC mode, which for AC means that the compressor clutch gets periodically engaged and disengaged to ensure proper operation of the compressor and evaporator without anything freezing over.



No. It is not correct to say that the system will "activate when the system requires it to for air cooling", regardless of what the SA told you. (Apparently, you and/or him misunderstood something in that manual).

The purpose of AC unit is not even remotely limited to cooling the air. The purpose of AC unit is to cool and dehumidify the interior air. For this reason, when you enable AC (regardless of Auto or Manual mode) it will run continuously (as I described above) even if cooling is totally unnecessary for achieving the requested target temperature. For example, if you ask the CC system to warm up the interior air with the AC still enabled (the green light lit up), the CC system will continue to run the AC. In this case the AC will cool and dehumidify the air, and then the heater will reheat the air again to the requested temperature. The CC system in this case knows that the AC is not needed for cooling, yet it assumes that you enabled the AC unit specifically to dehumidify the air.

This is actually pretty easy to verify in practice. Start the car and let it idle with AC off. Crank the temperature control to full heat, all the way up. Now activate the AC by pressing the snowflake button. According to what you said, the AC should not engage, since "it is not required" in this case. However, in reality it will engage immediately in 100% of cases, which is easily felt and heard when the car is idling.

In fact, there's currently no car [I know of] on the market that can activate/deactivate the AC automatically, on request of CC system. All CC systems in every car I saw work the same way with regard to AC: you can only disable or enable the AC manually. You turn it off - it stays off. You turn it on - it runs all the time. I don't know the exact rationale behind this. It might be something safety or fuel-economy related, I guess...

Again, "Auto" mode has nothing to do with controlling the temperature and/or AC. "Auto" mode controls only the fan speed and air stream distribution between the three levels. So, it is really "Auto Fan" mode and nothing else. This is why "Auto" mode can be enabled/disabled indirectly through the three air distribution buttons on the left end of CC control panel.

You and I agree on how the AC system works. I was replying to accel's original comment. He stated that when the ac indicator light is on, the system runs "constantly". As you and I agree, this is not the case; no AC system runs constantly. And as I stated the light means the AC compressor is "available" to turn on and condition the air when the system determines it is required.

[Rhodes7586]

Originally Posted by AndreyT

They actually just slow down. And with auto-sensing wipers it will depend on how much water there is on your windshield, not on the car speed.

That is correct.

Originally Posted by AndreyT

Is this really different from simply pulling the inside handle twice and opening the door?

Yes, it is different.

Originally Posted by AndreyT

Must be a part of Comfort Access...

Originally Posted by AndreyT

I don't think this is accurate.

It's in the manual. Page 110.

Originally Posted by AndreyT

Well, you can also press the clock button on the radio to check the current time. This doesn't just power up the radio, this seems to power up the entire car (i.e. power seats start working again and everything else)

Both ways work.

Originally Posted by AndreyT

Coupe only?

Not sure.

Originally Posted by AndreyT

"Headlights are on"? No, there's no need for headlights. When the cruise is active, the little marker is always there, perfectly visible regardless of headlights. Turning on headlights only makes it backlit, just like the rest of the cluster.

You are right.

Originally Posted by AndreyT

What you will get will depend on the type of disc you have in the player. If you have an ordinary basic Audio CD in there, there's no chance to see the track names - the radio does not know the track names, which is why it can't possibly display them. (Enhanced Audio CD formats can supply this information though).

MP3 CDs display file names (not track numbers) in "normal" mode as well as in list mode, i.e there's no difference.

There's also the third mode: INFO mode, in which the radio displays the song and album name retrieved from the MP3 tags stored inside the MP3 file.

Also correct

Originally Posted by AndreyT

This is, like, a well-known feature of virtually all automatic-transmission cars. I'd be surprised to find out that in this age they still implement it with something as primitive as a plain button behind the pedal. Do they?

[AndreyT]

Originally Posted by Rhodes7586

It's in the manual. Page 110.

Nothing like that in my manual. Page 110 says

"On inclines, do not hold the vehicle for a lengthy period using the clutch; use the parking brake instead. Otherwise, greater clutch wear will result"

This quote refers specifically to the habit of "holding" the car on the incline by feathering the clutch. I.e. people would depress the clutch pedal partially to create the exact amount of clutch friction necessary to prevent the car from rolling back. No argument, this is a very bad habit, which will result in accelerated clutch wear. But that does not say that the clutch remains partially engaged when the pedal is fully depressed.

In another paragraph it says

"Never drive with the clutch held down, with the transmission in neutral or with the engine switched off; otherwise, engine braking action will not be present or there will be no power assistance to the brakes or steering."

So, neither quote supports the claim that the clutch never fully disengages. Just in case I searched the whole manual for "clutch" and found nothing to support that claim.

It is often postulated that holding the clutch pedal depressed for extended periods of time is detrimental to the lifetime of clutch release bearing ("throwout" bearing), but even that is something that is more applicable to older clutches than to the modern ones.

As for the clutch staying partially engaged even when the pedal is fully depressed... No. Something like that would mean that the clutch is not adjusted properly. And it would be immediately noticeable, since casual (non-rev-matched) attempts to shift gears would produce a lot of grinding.

[achien]

actually, if you do normal up-shifts (i.e. from 4->5, or 5->6), it will rev-match too.

Originally Posted by John 070

Learned something today, when you're on cruise and you step on the clutch, the cruise reengages when you let off the clutch. On my Nissan the clutch disengages cruise altogether.

[achien]

yes, it's called "pumping" the brakes. the old-fashion way to avoid locking up your wheels before ABS became the standard feature.

this is a "lost art", only the old folks know how to do this now.

Originally Posted by DUI Elite

Is there any way to turn off ABS?

[AndreyT]

Double-clicking the "Audio" button on the radio makes it switch to the next audio source (i.e. Tuner to CD, CD to AUX and so on).

[SD ///M4]

Originally Posted by AndreyT

That's pretty typical for all cars since the beginning of times. I remember that once I forgot to turn off the headlights in my '88 Civic. When I came back several hours later they were off. I don't know how long it took either...

I don't know when "beginning of times" is for you, but I'm just going to guess that I've been driving for a lot more years than you. In the dozen or so cars I've owned since 1965 I've never had a car before this that would automatically turn off the trunk light. I also have an S2000 and the trunk light will not turn off on it's own. Trunk lights used to have switches on them but those have disappeared, probably a result of cost cutting.

Headlights are a different thing. They didn't use to turn off by themselves and many people would accidentally leave them on and drain the battery. Then they started introducing warnings that would chime if the headlights were on when the ignition was turned off. This is what my 2000 S2000 does. Having headlights turn off automatically is a fairly recent feature, maybe in the last 10 years. If my 2000 S2000 doesn't have an auto-off feature, and my '96 Integra GSR and my '88 Prelude didn't, I'm pretty sure that your '88 Civic didn't, regardless of what you remember.

[AndreyT]

Originally Posted by SD 335is

...I'm pretty sure that your '88 Civic didn't, regardless of what you remember.

My post was a joke, referring specifically to an incident when I forgot to turn off the headlights and drained my battery.

As I said, it was always that way: if you forgot to turn off some light in the car, it would turn off by itself "eventually". Oh, well...

[SD ///M4]

Originally Posted by AndreyT

My post was a joke, referring specifically to an incident when I forgot to turn off the headlights and drained my battery.

As I said, it was always that way: if you forgot to turn off some light in the car, it would turn off by itself "eventually". Oh, well...

I was actually going to ask if you had forgotten that it also drained your battery!

A would have made your post the wry statement that it tried to be.

[FlowState]

Originally Posted by achien

yes, it's called "pumping" the brakes. the old-fashion way to avoid locking up your wheels before ABS became the standard feature.

this is a "lost art", only the old folks know how to do this now.

wish there was a way to do it without only confusing the computer like this. I'd rather have the computer not try to pulse at all rather than fight it. I loved driving with no ABS. Felt so much more in tune with the car.

[InsanePineapple]

Not sure if this has been mentioned, but I just recently learned that the fuel door locks/unlocks based on whether the car is locked or unlocked

[Bimmer84]

Originally Posted by morfinx

Not sure if this has been mentioned, but I just recently learned that the fuel door locks/unlocks based on whether the car is locked or unlocked

Pretty much common sense man! But I am sure others didn't know either... Many (newer) cars are this way though.

[Tuna_Flake]

Hello, Thankyou for this great thread.

I'm picking up my new to me 2008 320D on saturday!

Just want to thank everyone who has posted. I've Spent a good 3 hours (on/off) reading this thread while at work! hahaha.

cheers
Paul.

[FlowState]

Dunno how many know this, but

You can run your car without your key even if you don't have comfort access.

1) Press Brake (+ Clutch) and press Start/Stop with key fob in.
2) Turn it off and remove fob while still holding brake (+Clutch).
3) Press Start/Stop button without key fob in

and your car will still start up. Theres like a 5 second window where you can start the car without the fob. I do this in winter if its very cold. Lock the car and let it warm up (or stay warm) outside if I'm just stopping for a few minutes.

[bmwjunky]

Good to know DUI Elite, thanks!