New front suspension, no leaks but compressor runs
04-17-2013, 02:41 AM
#11
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How often does the computer tell the compressor to come on?
A while back my rears weren't holding air. Over night both sides would be way down. So I bought some gen I's and I'm ok now for the bags holding air. However, it seems like the compressor runs nearly as much as it did before the air bag install. I would have thought the demand for the compressor would be way down now.
Does the compressor kick in based on the height sensors?
And how does it work? The compressor fills the pressure tank, and the tank tolds pressure to the bags? Never really knew how all that works.
In any event, how often would you say all yours runs?
A while back my rears weren't holding air. Over night both sides would be way down. So I bought some gen I's and I'm ok now for the bags holding air. However, it seems like the compressor runs nearly as much as it did before the air bag install. I would have thought the demand for the compressor would be way down now.
Does the compressor kick in based on the height sensors?
And how does it work? The compressor fills the pressure tank, and the tank tolds pressure to the bags? Never really knew how all that works.
In any event, how often would you say all yours runs?
04-17-2013, 06:18 AM
#12
AudiWorld Member
Read this .pdf that goes over the allroad air suspension. The part about when the compressor comes on is on page 19 but the whole thing is a pretty good read to understand what is going on.
http://www.volkspage.net/technik/ssp/ssp/SSP_243.pdf
Here the section I'm talking about:
I only hear my compressor come on if I'm changing ride heights manually or it's a particularly cold morning and the air bags have contracted enough to warrant the compressor. I know it comes on periodically while I'm driving but I don't notice it come on.
http://www.volkspage.net/technik/ssp/ssp/SSP_243.pdf
Here the section I'm talking about:
At driving speeds of < 36 km/h air supply is
effected primarily by the pressure
accumulator (provided sufficient pressure is
available).
The pressure accumulator is only filled when
driving at speeds of 36 km/h and above.
At a driving speed of > 36 km/h the air supply
is primarily from the compressor.
This supply strategy ensures virtually
noiseless system operation and reduces the
current consumption.
The pressure accumulator allows the vehicle
level to be raised more rapidly with minimal
noise as the pressure accumulator is only
filled while the vehicle is in driving operation
and the compressor noise is less noticeable
(see air supply strategy).
Provided that there is sufficient pressure in
the pressure accumulator, vehicle level
raising can be performed without the
compressor.
Sufficient pressure means that before the
vehicle is raised there must be a pressure
difference of at least 3 bar between the
pressure accumulator and the air springs.
The pressure accumulator is made of
aluminium and has a storage volume of
approx. 6.5 l. The maximum operating
pressure is approx. 16 bar.
effected primarily by the pressure
accumulator (provided sufficient pressure is
available).
The pressure accumulator is only filled when
driving at speeds of 36 km/h and above.
At a driving speed of > 36 km/h the air supply
is primarily from the compressor.
This supply strategy ensures virtually
noiseless system operation and reduces the
current consumption.
The pressure accumulator allows the vehicle
level to be raised more rapidly with minimal
noise as the pressure accumulator is only
filled while the vehicle is in driving operation
and the compressor noise is less noticeable
(see air supply strategy).
Provided that there is sufficient pressure in
the pressure accumulator, vehicle level
raising can be performed without the
compressor.
Sufficient pressure means that before the
vehicle is raised there must be a pressure
difference of at least 3 bar between the
pressure accumulator and the air springs.
The pressure accumulator is made of
aluminium and has a storage volume of
approx. 6.5 l. The maximum operating
pressure is approx. 16 bar.
04-18-2013, 06:17 AM
#14
AudiWorld Super User
Once it fills up the air tank, it is full and the compressor should stop running, even if you're driving above 35 km/h or so.
04-18-2013, 06:33 AM
#15
AudiWorld Member
I am going to attempt to re-calibrate my sensors position today or tomorrow to see if that is what I got going on. I am 402ed so my question is, when I enter the suspension module and the AR goes to L2 automatically does that mean that at that moment the sensors have all reseted themselves or will I have to fiddle around with each corner to get it right?
04-18-2013, 10:10 AM
#16
AudiWorld Super User
I am going to attempt to re-calibrate my sensors position today or tomorrow to see if that is what I got going on. I am 402ed so my question is, when I enter the suspension module and the AR goes to L2 automatically does that mean that at that moment the sensors have all reseted themselves or will I have to fiddle around with each corner to get it right?
It goes to L2 based on current sensor readings. It doesn't recalibrate itself, you have to do it one corner at a time, just like you did the 402.
04-18-2013, 06:26 PM
#17
AudiWorld Member
I was hoping that once I enter the calibration mode the sensors would rest to factory default. Oh well, see what I get tomorrow.
04-18-2013, 07:14 PM
#18
AudiWorld Super User
04-19-2013, 08:42 PM
#19
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Having the exact same problem, except my compressor doesn't turn off until I come to almost a complete stop (maybe <5-10mph?). Just installed Gen II Arnott bags and Bilstein shocks. Don't think I have any leaks. Haven't checked, but the system seems to hold pressure (does not leak-down in any position overnight). VagCom revealed the following codes though:
Address 34: Level Control Labels: 4Z7-907-553.lbl
Part No: 4Z7 907 553 E
Component: - 2C1A1 D040
Coding: 25500
Shop #: WSC 09999
VCID: 479D8DC0651C3020A06
2 Faults Found:
01772 - Signal from Level Control Pressure Sensor (G291)
27-10 - Implausible Signal - Intermittent
00775 - Level Control System Sensor; Right Rear (G77)
57-00 - Electric Circuit Failure
Address 34: Level Control Labels: 4Z7-907-553.lbl
Part No: 4Z7 907 553 E
Component: - 2C1A1 D040
Coding: 25500
Shop #: WSC 09999
VCID: 479D8DC0651C3020A06
2 Faults Found:
01772 - Signal from Level Control Pressure Sensor (G291)
27-10 - Implausible Signal - Intermittent
00775 - Level Control System Sensor; Right Rear (G77)
57-00 - Electric Circuit Failure
04-20-2013, 04:11 AM
#20
AudiWorld Super User
Having the exact same problem, except my compressor doesn't turn off until I come to almost a complete stop (maybe <5-10mph?). Just installed Gen II Arnott bags and Bilstein shocks. Don't think I have any leaks. Haven't checked, but the system seems to hold pressure (does not leak-down in any position overnight). VagCom revealed the following codes though:
Address 34: Level Control Labels: 4Z7-907-553.lbl
Part No: 4Z7 907 553 E
Component: - 2C1A1 D040
Coding: 25500
Shop #: WSC 09999
VCID: 479D8DC0651C3020A06
2 Faults Found:
01772 - Signal from Level Control Pressure Sensor (G291)
27-10 - Implausible Signal - Intermittent
00775 - Level Control System Sensor; Right Rear (G77)
57-00 - Electric Circuit Failure
Address 34: Level Control Labels: 4Z7-907-553.lbl
Part No: 4Z7 907 553 E
Component: - 2C1A1 D040
Coding: 25500
Shop #: WSC 09999
VCID: 479D8DC0651C3020A06
2 Faults Found:
01772 - Signal from Level Control Pressure Sensor (G291)
27-10 - Implausible Signal - Intermittent
00775 - Level Control System Sensor; Right Rear (G77)
57-00 - Electric Circuit Failure
It looks like one of your wheel sensors is malfunctioning too. Bad contacts or needs replacement.