4x4 F-150 will not engage
Senior Member
Joined: Jul 2004
Posts: 6,200
Likes: 39
From: Easton, Pa.
If you still show a ground, the lead going to the solenoid from the case motor plugup is grounded by a pinch or a rub-through in the harness..
You have to look at the color code and trace it's path between the two points.
This ground will prevent the 2wd solenoid from allowing vacuum to be applied by the other solenoid for 4wd when the ignition is On..
One solenoid pulls the Actuator diaphragm 'out of 4wd' with engine vacuum, the other does just the opposite with engine vacuum >>> when each gets the ground through the case motor operation for the requested function in a fault free system.
You have to look at the color code and trace it's path between the two points.
This ground will prevent the 2wd solenoid from allowing vacuum to be applied by the other solenoid for 4wd when the ignition is On..
One solenoid pulls the Actuator diaphragm 'out of 4wd' with engine vacuum, the other does just the opposite with engine vacuum >>> when each gets the ground through the case motor operation for the requested function in a fault free system.