4wd light goes out when head lights are turn on

[firstx]

When i put my 96 explorer sport on 4wd, the light lights up but when i turn the head lights on the 4wd light does out. I went on a dirt road with the light on and gave it a lot gas and the back tires didn't spin as fast as it was was in 2wd. When i gave it alot of gas with the 4wd light out with the head lights on it did the same as if it was in 4wd.

So why is it doing this and why is the 4wd still working even when the light is out. I put in 4wd low and it works with the headlights on or off.

Bob

 

[budwich]

maybe cause the 4wd control module doesn't know about your light problem only that its controlling your 4wd effort...

Likely problem is the light switch... but check it with a meter to ensure proper voltages are entering and leaving.

 

[firstx]

Do i check at the 4wd switch or the headlight switch.