Galaxy AHU: Atmospheric Pressure Explained

Hello,

I'm currently experiencing a very interesting problem with a 1997 Galaxy 1.9 TDI (90hp) with the AHU engine.
FSP entry => Intake manifold pressure control differential
It's not a particularly interesting (or rare) error, but I think I'll mention it.
Sure, here is the translation:

"Here are a few details about it:"
The problem occurs sporadically, only after the engine is turned off and restarted (whether the engine is cold or warm).
Whether or not the NL (National League) game has been played is irrelevant.
If the error occurs during load application, the problem already existed during motor start-up.
Target boost pressure in low load (LL) is approximately 620 mbar?!?! The actual value in low load is normally around 980 mbar.
=> Delta in the supply pressure setpoint is approximately 400 mbar and remains the same on the return side (at approximately...).
3000 RPM instead of 1830 mbar, 1430 mbar. With such a low LD (light distribution), it cannot be properly adjusted.
Reaction => FSP entry.
The atmospheric pressure in MWB10 is constantly at 693 mbar (=> highly implausible).
at an altitude of 400 meters above sea level.
LD was checked using a manual pressure/vacuum pump in MWB 10 and 11, and it showed that...
with a detached hose, the pressure is approximately 980 mbar, and it responds perfectly to pressure changes.
Vacuum application.
Another FSP entry: SG defect (65535 037).

Diagnosis: Atmospheric pressure sensor (in the SG?) is defective. I will check it out right away.
"However, in the Galaxy, the SG (likely referring to a specific component) is positioned rather awkwardly behind the instrument cluster."

Can someone confirm whether the ADF (Automatic Distress Signal) is located in the MSG (Main Storage Compartment) of this vehicle?
And what I'm really curious about is:
why is the LD setpoint (with a constant, incorrect ADF value of 693 mbar)
sporadically after engine start, the idle speed jumps to a plausible value of approximately 1000 mbar.
(and everything is fine, I can drive hundreds of kilometers with it!), and sometimes on the described [road/route].
The value triggering the error is approximately 620 mbar.

Best regards, PD90.

Hello PD90,

Check out this post:

/viewtopic.php?t=19228&start=24

Best regards, Christian.

I once had the exact same problem. I then replaced the ADF and, when that didn't work, also the LDS in the control unit, but without success. The problem was somewhere in the circuit and couldn't be fixed with a reasonable amount of effort. So, I replaced the control unit, and everything was okay.

Thank you very much for your initial reactions.
I just finished reviewing the linked post by servuss.
It's very similar to the problem I'm having, but unfortunately, I couldn't find it in my search.

First of all, I will examine the original MSG and focus on...
Check for bad solder joints, but I'll get to a follow-up question shortly.
(whose answers I hopefully won't need ):

had a completely identical vehicle with engine damage that could be used as a source of spare parts.
"The car has an MSG (Message System), a combination instrument panel, and an ignition switch, all of which are present and functioning perfectly until the engine fails."
have occurred (damage => water damage...).
If addressing the issue of "re-soldering ADF in the original MSG" doesn't lead to a successful outcome, then...
Could you please give me some tips on MSG trading and WFS?
Do I need to replace all 3 components (MSG, combination unit, and ignition switch)?
Can I transfer the WFS (Wireless Fleet System) from the donor vehicle, or can I connect the WFS from the donor vehicle's MSG (Modular Service Gateway) to the "new" vehicle?

Sorry, WFS is not exactly my area of expertise.

Greetings, PD90.