The double traction lever reaches its position? or is it halfway?
If the lever enters the 4H or 4L and the witness turns on, the failure can be on the front bushings, sometimes the fat of the buses is hard and the carraca or free wheel system that they carry does not hook or does not release once you put the 4x4.
If it does not hook, it usually does a clack clack clack clack clack and if it does not release, what happens is that when you put the 2H the car goes hard, as it stops and it is because it is still moving the entire traffic system, to release it when it does that you have to go back and walk a couple of meters (or more ...) and the clack clack clack clack clack clack clack clack until it is released.
The solution is to disassemble the front bushings, wash them well with diesel or gasoline and put new and lighter fat in the free wheel mechanisms.