04 FX4 s-cab-"4x4H" only flickers when I shift on the fly to 4H, so I never really know is it in or out of 4x4??? The wiring diagram shows a "four-wheel drive control module"in circuit with this indicator. Does anyone know where this is located and what the chances of this being the culprit??





thanks

 

Your IWE vacuum solenoid has shorted out, or the transfercase motor has corroded. My vote is for the first explanation. the solenoid often gets water in it because it is located directly below the cowl on the passenger side right behind the battery on the firewall.

There is a replacement part that has a 'rain shield' built on it, from your dealers parts counter.

6L3Z-9E441-A IWE Solenoid

 

The only thing though, is the truck is shifting in and out of 4x4, it just wont give the indication at cluster??