07 A8L 4.2 Source of signal(2) for Leak Detected code generation.
 

Would like to find out what signals the suspension system controller gets to activate the "Leak Detected" code. Looking through the manual has been difficult.

About a year ago, at about 60k miles, the front went down to the stops and we replaced the compressor with an amazon type, not the dealer type. We could tell the compressor had overheated and remember getting a burning odor before taking it out. The problem was solved...until it wasn't. Now, the same thing happened. We tested the compressor and it was bad (runs OK but no pressure). By now I had installed a new piston ring on the old compressor and it produced about 260 psi, so we re-installed it. This solved the problem...again, for now.
I sprayed soapy water everywhere and can't find a leak. But the compressor rarely runs and only for a minute, maybe once per day?

When the problem happened, these are the :evel Control issues found: I'm trying to find out where the signal come from for "01583 - Leak in System Detected".
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Address 34: Level Control Labels: 4E0-910-553.lbl
Part No SW: 4E0 910 553 H HW: 4E0 907 553 F
Component: LUFTFDR.-CDC H06 4480
Coding: 0015510
Shop #: WSC 02313 785 00200
VCID: 2809FB8B3EFDB2C7194-807C

4 Faults Found:
01400 - Suspension Level Control
002 - Lower Limit Exceeded
Freeze Frame:
Fault Status: 11100010
Fault Priority: 2
Fault Frequency: 104
Reset counter: 45
Mileage: 101475 km
Time Indication: 0
Date: 2018.05.04
Time: 20:09:53

01598 - Drive Battery Voltage
002 - Lower Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 4
Fault Frequency: 1
Reset counter: 84
Mileage: 102990 km
Time Indication: 0
Date: 2018.08.29
Time: 01:54:57

01583 - Leak in System Detected
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 3
Fault Frequency: 28
Reset counter: 83
Mileage: 0 km
Time Indication: 0

01577 - Turn-Off due to Over-Temp
001 - Upper Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 4
Fault Frequency: 2
Reset counter: 59
Mileage: 102362 km
Time Indication: 0
Date: 2018.06.10
Time: 14:19:08


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