4 wheel drive high blinks on for a sec then goes off

[mechcom]

Hi all new to this forum,
My question for help is I have a 2005 expedition xlt hust bought it.When I put it in 4 wheel drive the high lights blinks on for a second then turns back off.When I put it in 4 wheel drive low light comes on and stays on as it should.Both high and low lights come on when initial start of vehicle is done and go out.The transfer case is engaging in 4 wheel drive high and stays in but my light goes out Help Please want to fix this

 

[bedrck46]

the 4H and 4L Lights get their signal from the PCM could be some bad wiring or ground or a problem in the PCM

 

[bedrck46]

The instrument cluster 4L and 4H indicators do not operate correctly/do not operate/flash

Instrument cluster.
Circuitry.
4x4 module (PCM)

 

[mechcom]

The Low light operates as it should the high light comes on for a second then goes out and transfer case is in 4 high