I had a look at this car today. It was as described - self level warning on, no codes and rear was bouncy. Turns out the car had been put in "Line Mode". It was referred to as "Mode, end of line" in another section of the GT1. I suspect this is the mode it goes in when it comes off the assembly line. There was another mode called "Transport". Transport Mode was off and Line Mode was on. I deactivated Line Mode (it was called yet another thing in the deactivate menu), the error message went away and the truck drives like it should.

So, if SLSI error message is on, no codes, no sagging suspension and the truck rides bouncy, check if it has accidentally been put in Line Mode.

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Daily Drivers:
- 2008 535i, 320,000km
- 2004 X5 4.4, 01/2004 production, 420,000km
- 1997 328i, 350,000km

Track:
- 1996 328i, track/race car, ~300,000km

Winter:
- 2013 Ski-Doo MXZ X 800 E-TEC, trail can
- 2007 Ski-Doo MXZ Blizzard 800 HO
- 2001 Ski-Doo MXZ 600 w/800 engine, exhaust
- 1978 Ski-Doo Olympique 340 (vintage race sled)
- 1977 Ski-Doo Olympique 340E