Hi guys,

I just purchased a 97 F150 4x4. The guy told me at the time I purchased it that the 4x4 didn't work and that he thought it was the switch, he had recently replaced the actuator. I'm sure the axles and diff are good as there is no vibration from the front and the axles are in great shape. The switch does have power to it because at night it lights up. Is there a better way to troubleshoot this? Is there some kind of electronic tool that I can plug into the 4wd cable (I have the switch pulled out) to test and make sure the actuator was installed correctly? Would the switch still light up if it was dead? I'm trying to avoid just getting a new switch cause the cheapest I've found them is 80.00 and I don't want to spend that if that's not the issue. Sorry for typing so much just really want to get this figured out since it's Feb and I live in Michigan lol.

Thanks!

 

there are two solenoids behind your battery, mounted on the firewall with vacuum lines running into them. one engages 4x4, one disengages it. our trucks have a problem with those vacuum lines breaking, and if the light comes on and everything else seems to be in good condition, that would be my guess.

i was in the exact same situation with it as you, even had my entire 4x4 assembly apart once and it all looked great, but it wouldnt engage. i found that under the battery, both vacuum lines were snapped in half, it looked as if they had been eaten through by a chemical, or maybe just got old. replaced them in 30 minutes and it was good as new. just dont get the colors mixed up if thats the problem. it could be the switch, but i know the vacuum lines are a common issue. worth a shot to check if you havent.

*also, i used a combination of flexible line and hard plastic OEM style line to redo it. the line rubs on the platform holding the battery, and by using the flexible line i routed it differently to avoid the problem happening twice.

 

Thanks Colton,

I'll check that tomorrow during the daylight. I'm actually not even getting 4x4 light on the dash. Which makes me think it's the switch or something electrical.

 

i have the floor shifter, but i have heard there is basically no difference between that and the switch, aside from the looks of them. you might as well check the vacuum lines just to be sure, but if the light doesnt even come on then it may be the switch. i wonder if you could pull the switch out of the dash, and test the wires that engage the 4x4 to see if any current goes through them? im not sure exactly how the switch would work, but im sure someone on here would.

 

Yeah was hoping someone on here could help me figure that out. I've already pulled the old switch off. There is an autozone down the street from me. I wonder if they can do it like they can with their code scanner. Does anyone on here know if/how I can run a current through the wires for the 4wd switch? I've pulled the switch.

Thanks!

 

Nine times out of ten the actuator motor is at fault. Does the dash light prove out when you turn the key to run?

 

The 4x4 light does come on when I turn the key to acc. When I turn the 4x4 switch none of the lights come on.

 

when you put the truck in 4x4, what makes the dash light come on? i dont see how it could be anything between the solenoids and the wheels, because when my vacuum lines were broke, my light still came on, however no signal went past the vacuum lines. is it the switch itself that makes the light come on, or is it something between the switch and the solenoids?

 

I would like to know this as well.


UPDATE: I just got a new switch off ebay. Having them overnight it to me so that'll be one thing out of the way

 

i had a fuse go out and replace the switch thinking that was it try the fuse if not the fuse check the wires going to the switch for a short good luck