2003 Nissan Pathfinder

Hello, I have a 2003 Pathfinder LE with 112K miles. I live in MA and 2 weeks we had our first significant snowfall. While I was driving 10 mps I decided to shift my car in Auto mode because I noticed that my back end was fish tailing a lil bit. As soon as I engaged it in auto I noticed smoke coming in from the passanger vent. Upon seeing this I immediatly switched it back to 2wd. 20 mins later I was trying to make my way up a hill and once again my car began to fish tail. I pulled over to the side of the road and put it in neutral and switched it into 4WD high. This time no smoke but I can tell it was not engaging in 4WD. I continued to make my way up the hill when I noticed on the dash diagram all 4 green tires began to blink as well as the yellow box and then they all turned off. Now none of 4 green tires as well as the yellow indicator lights turn on excpet when the Key is inserted and the 4WD light stays on.

I've told a couple of people what happened and they think that my transfer case might need replacing. The last time I switched the car into auto/4wd high/4wd low was last winter and I didnt have an issue. The car runs fine in 2wd.

Last week, I had the mechanic do a full tune up, brakes, changed the front 2 tires and had them change the oil in the transfer case and check all wiring. It looked like the issue was resolved, while the truck was on the lift the mechanic switched the suv into auto, 4WDH and 4WDL and back to 2WD. The garage was not able to hook the pathfinder up to the computer to run a diagnostic test as it was broken. The check engine light and 4wd Diagnostic light is still on which does not allow the wheel diagram to light up on the dash.

We had another snow storm the other day and the problem still persists; the auto, 4WDH & 4WDL do not work. I had a hard time just trying to get out of a parking spot

On a separate note, the 2wd and Auto do not light up on the switch located next to the ashtray. This occurred a couple weeks back. Only the 4wdH and 4wdL are back lit. I checked the see that the connection was secure and it was. Is there a fuse that needs to be replaced?