I have problem with the Mitsubishi montero rear wheel drive light left one it disappeared of the dash board while i was entering to my drive way the active skid control light began to flashes along with the rear wheel drive light then the light of the left one rear wheel drive it disappearded please help me on how to fix this problem thank you

Find where the ground wire for that left taillight grounds to the body remove the screw and clean that ground, otherwise if the taillight assembly uses a printed circuit could be a break in the printing, replace the whole assembly if thats whats going on.

This means there is a problem with the four wheel drive

I believe that Mitsubishi has one of the best and easiest 4X4 selector systems on the Pajero/ Montero. Just below the gear shifter lever is the 4X4 mode selector. A lever like the gear shifter that works in a up, down movement. On your dash board you will notice a sort of axle, chassis diagram in green light. In normal 2WD or 2H mode the lever is set all the way back and on the dash only the rear wheels a lite up in green light on the axle, chassis diagram. This is for normal driving on the highway and smooth roads of dry dirt roads. Pushing the lever up wards while moving at crawling speed will engage the light 4X4 mode which is 4H for when the driving gets a little slippery. All 4 wheels on the axle/ chassis diagram will be lite green. Shifting the lever from the 4H position to the left and upwards will engage the 4HLc mode for 4X4 on sand and deep snow. This will also engage the central diff lock which will show on the axle/ chassis diagram on the dash board with the center box also lite up. Further up from the 4HLc mode and while pushing down on the 4X4 lever push it to the top most position, but only do this when at a stand still with your foot on the brake pedal. This will engage the 4LLc mode with 4X4 and central diff lock on for when driving gets sweaty on thick mud up and incline. To disengage this mode stop, foot on break put it in P and then pull down the lever to one of the lower settings.

Look for a vacuum hose that did it for me

this is telling you there is an error with the 4x4

is it true that I have to put my montero in reverse to engage 4 wheel drive first?

well first you have to find out why it is low but it also needs to be vaccumed down before charging best left to shop with proper equipment

Run hot wire from battery stright to bat. side of coil and see what happens.

did you check the lock mechanism under the wheel at the dash? you have to relock the wheel it sounds like by pushing the lock lever

check your dimmer knob, it should be on your left hand side on your dash board, turn on your lights then turn it, if that does not solve the problem check your fuses