Self Adaptations Off?!
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MBWorld Fanatic!
Joined: Jul 2005
Posts: 3,176
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From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Self Adaptations Off?!
So trying to monitor Smooth running with Autel. Ive reset all adaptations and seems I have a clean slate although I see there are some modules that have requirement Self Adaptions are “On”. But in this instance they show red and “Off”. Does the car need to learn for a while for this to turn to “On” or what else should I change in the settings?
Car running pretty well but still getting this bloody annoying “P20D4 : The load limit is active (P1999)”. Supposedly its related to the throttle body but it also could point to a vacuum leak.
Any help please!??
PS running 82mm TB (another on the way).
Car running pretty well but still getting this bloody annoying “P20D4 : The load limit is active (P1999)”. Supposedly its related to the throttle body but it also could point to a vacuum leak.
Any help please!??
PS running 82mm TB (another on the way).
Last edited by stevebez; Nov 29, 2025 at 09:42 AM.
Thread Starter
MBWorld Fanatic!
Joined: Jul 2005
Posts: 3,176
Likes: 19
From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Its weird - it seems to be a bit of a catchall for vacuum leak throttle body flutter diesel injectors and others but quite common issue as part of P1999. So no idea.
Comes up for both diesel and petrol from what Ive seen. I actually think its picking up boost “out of range” of plausible on the overall map and tripping up. Thing is car feels and runs completely affected even when this is active.
Load limit though does not sound great!
This link is the only one Ive found that covers this
https://youtu.be/SnDB0hPu8oM?si=lk8jBqN8hD2NiivP
Even though its P20A2
Comes up for both diesel and petrol from what Ive seen. I actually think its picking up boost “out of range” of plausible on the overall map and tripping up. Thing is car feels and runs completely affected even when this is active.
Load limit though does not sound great!
This link is the only one Ive found that covers this
https://youtu.be/SnDB0hPu8oM?si=lk8jBqN8hD2NiivP
Even though its P20A2
Last edited by stevebez; Nov 30, 2025 at 05:03 AM.
Thread Starter
MBWorld Fanatic!
Joined: Jul 2005
Posts: 3,176
Likes: 19
From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Ive also seen wiring harness issues.
there is reference to implausible voltage on injector circuit B. So may have a dry connector , corroded wire, broken insulation somewhere in the harness (possible) but unlikely imho. Perhaps the injector is maxing out 100% duty and that triggers the fault as well (given high boost relative to the rpm) - perhaps having the boost higher up in rev range is more plausible - dunno reaching now but that's where I am at.
there is reference to implausible voltage on injector circuit B. So may have a dry connector , corroded wire, broken insulation somewhere in the harness (possible) but unlikely imho. Perhaps the injector is maxing out 100% duty and that triggers the fault as well (given high boost relative to the rpm) - perhaps having the boost higher up in rev range is more plausible - dunno reaching now but that's where I am at.
