4x4 High engaging on its own

[MicNichole]

I've seen a few posts about getting stuck in 4x4 low but when I'm driving down the road my 4x4 high comes on, on its own and the controls on the dash don't turn it off. The only thing that turns it off is to turn the truck off and back on and then its only a matter of time before it turns itself on again, ever since this has started the ABS light on the dash comes on occasionally too???

 

[FordFool2]

Sounds like you have an ABS wheel sensor that is going bad.

 

[lukiss99]

Check your tyres for wear, inflation pressure etc.
I had different brand tyre on the front when I bought my explorer and it was enough to upset the 4WD computer. I had to remove the fuses to prevent it going into 4WD until I had the tyres all replaced.

 

[MicNichole]

The front passenger tire is actually the spare tire, it didn't have the forth rim when I bought it?

 

[lukiss99]

Does the tyre on the "spare" look like is has more tread compared to the others? If the rolling diameter is different then it will cause issues.