why wont my four wheel drive engage, worked great last year and now nothing
check the 4x4 fuse,switch to 4x4 could be bad,it also has a small motor on back of transfer case it could have come unpluged or gone bad.
if the 4x4 light comes on do you think it may still be as simple as a fuse?
yes it could be,the 4x4 fuse is usualy in fuse box under dash,some are under the hood fuse box it will say 4x4 on fuse pannell,also you may want to have the hub assem on front to be checked to see if splines are striped,if just not enguadeing,fuse or the motor mentioned in other post.ford is bad for this motor going bad.
Thanks a lot, I really appreciate your prompt and knowledgable answers. You are a blessing!
No problem,hope I was of some help,let me know how it turns out.
mine was maddening, and was a corroded conductor under the hood. Pull the codes and see if you have a shift relay code. But check your fuses and the shift relays under the hood. Its a pair that fwd/rev the polarity to the shift motor to engage/disengage the 4x4......IF your fuses are good and IF youve replaced both relays under the hood (you can temp swap w any other of the relays under the hood they are the same) then look at the drain hole under the relay housing and look for any whitish green powder around the drain hole. Its a clear indication of copper corroding.....dissassemble the housing and repair.....
where are the fuses located dont have any lables on fuse panel
good question mine either but i do numer 17 is one of them, it is a large fuse under the hood'
30 amp inch wide
my f-250 will not come out of 4x4 and it wont start
i have replaced the shift motor the dash switch and the relays. the truck is stuck in four low. HELP!!!!!
look under the two shift relays under the hood, likey you will find white/greenish powder around the drain hole under the assembly. here a conductor has corroded through and wont allow you to shift out. additionaly, truck must be in neutral to shift out of low4x4. you can remove the shift motor and shift it out with a cresent wrench on the shift shaft. make sure its in neutral, parking brake on.
i give that a shot. the thing i do not get is the dash light is saying its not even in four wheel
ralays are clean and greased and still nothing
the issue is in the position switch then, near the shift motor, it gives the feedback loop back. the factory sm gives a full step by step pin point test for all those conductors. I dont have my 99 f250 anymore, dont need the manuals, its a stack of books about 10" high that cover everything on that truck, yours for 120$ plus shipping if you want them.
OR, it may still be the dash switch, pry the cover off one shift relay, ensure both are in their sockets, and push on the tab of the relay....it should shift the 4x4, If not, switch the relays from one socket to the other and try again. you will have top swap them to get it to go to the opposite direction or just pry the covers off both and see if it will switch back and forth with your thumb on the contactor of the relay...if it does your issue is in the dash switch.......mj
Thanks for the help
I just ran into the same problem I looked it up and clicked my way to this thread and I already did everything that was said so have you figured out the problem
To eliminate a control issue. Pull the cover off two shift relays and push the contactor with your finger alternating from one to the other. That bypasses all controls and control power. ....do that and let me know what you find.
Jackmanmachine...I'm having the same problem with my 2010 F150 where dash control knob seems to do nothing. Also, no indicator lights come on in the info screen saying 4x4 hi or Lo. I've been wondering if it's the switch itself or something else. Trying to narrow down what's causing the issue and will need 4WD soon. Where are the shift relays? Any other suggestions on what to check?
dont know on the 2010, google the location, but you get no feedback untill the shift motor makes, IF its the relays, thats simp[le to check the same relays are used all over the ford, just swap with another and see if you get control. IF nothing changes and IF the relay fuse isnt blown then I would gently pry the cover off two relays , place them in the shift sockets and with my finger push the contactor in till it makes. if its in your wiring then the trans will shift..
Great. Thx. I will try this first and post what happens.
Okay I have. F250 4x4 was working great turned it off now no 4x4 light will light up ant ideals ?
jackman, we can manually shift with the covers off the relays. but no power to switch on the dash. what to ck next?
Lift the block the relays are plugged into, look for greenish white powder around the drain hole. If none then open and inspect the inside, beneath the relays. Look for any signs of corrosion. Your problem is prob there. The step after that is to open the harness at the shift motor and with a multi meter do a point to point continuity check on the conductors from the shift motor to the switch and relay sockets. I'm betting corroded wire under relay
The wiring from the relay to shift motor is good. Fuse and wiring to relay is good. No current to switch and dash light indicator is not on. Control module has been replaced. (used unit)
If you've done the continuity test but not looked under the relays to verify you not done. On my it PASSED the continuity test. When the probe was pushed into the relay socket the downward pressure was enough to close the open circuit. .. you have to look under here.
we took the the bottom off the the relay box under the hood, by the fuse panel. Its clean no corosion.
then if im understanding this? youve validated all the wiring with a point to point test? (this takes two people with long test leads on the meter to do) AND youve replaced the position indicator under the truck AND all the relays are good, all the fuses are good and you still dont have voltage at the switch in the truck....? as unlikely as it can be the only thing left is the GEM module.....about 230$ IF you go this route my recommendation, have the dealer instal it, if it doesnt correct the problem then make them take it back, they will bitch but since they put it in and the problem wasnt solved then they have to take it back. or find one on ebay. there may also be a battery saver relay and another relay involved, I have to wait and when I get home look at my service manual to be certain. what year is yours??
We did not do a point to point test, we didnt have a diagram. When looking for an online wiring diagram I ran across this site. Some the posts seemed close to my problem. Cant blame a guy for looking for a quick fix. I do have access to alldata and plan a more educated search tomoro. Thanks Johnny
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