I have a 98 ford ranger that sat for a while after i wrecked it. i started it back up and the 4x4 does not want to engage when i turn the switch. right when i start the truck the dash lights start flashing 2wd and 4wd. that stops after a while but when i go to turn on my 4 wheel drive it does not do anything and the lights blink again. does anyone have any idea what could be causing this?