Symbol 3626 from ISO 7000 - Title/Meaning: Rear step ladder Function/description: To identify the control that operates the rear step ladder. To indicate the operational status of the rear step ladder.
Additional information: 
The truck cabin icon may be omitted if not needed
Arrows may be added to indicate the movement directions.
Own work using: iso.org/obp/graphics/grs/c074f545-bad4-42ca-8563-2a7956c75e6e 200.png
Vectorization:  Mrmw