4wd does not turn off

[rob bassett]

i saw a couple of posts regarding this, but my issue is slightly different, so hence the new post.

used 4wd quite a bit over the weekend, with the snow we got here in MA.

no problems ever before, but this morning as i pulled out the driveway and went to turn OFF the 4wd, it did nothing. in other words, i moved the switch from 4high to 2wd and heard no click, and the truck stayed in 4high AND the 4wd light stayed on in the dash.

from what i've read, it would seem that the lack of a click means the 4wd module could be bad, but i am not sure since the light remained on. (so far every other person with a bad module said the light went off (so it appeared to be in 2wd mode) but the 4wd was still engaged. in my case, it does not disengage and knows it's not disengaged. i'm tempted to think it may be the switch.

also- it does not engage 4low either. so that also leads me to believe the switch could be faulty.

any suggestions? (any way to to at leat jump the switch connectors to tell it to go to 2wd?)

 

[Todd Z]

Try leaving the switch in 2wd and back up the truck 2-3 feet....

Maybe the shift fork in the t-case is stuck from the drive train and it did not release...



Just a thought..



Todd Z

 

[rob bassett]

i had left it engaged in 4wd high overnight, as i have done before in storms, to (ironically) prevent it from being stuck in 2wd and not engage 4wd.

it's thawing in the parking garage. i'll find out tonight if it unsticks. (thanks about the backing up suggestion; i didn't think to try that as i only remember that as for the older explorers)

 

[Todd Z]

If that does not work the electronics may have been damaged from leaving it in 4wd....

I know it has worked before, but the battery and things may have been 100% at that time...



Also it seems the module goes if you play around with the battery, alternator, or jump people the wrong way..



Todd Z

 

[Chris Taylor]

I agree with trying to let it warm up, but if you hear no click, the relay is not working, and that's part of the module... I've left mine in 4H overnight and even for several days in a row with no problem. Nice Christmas present huh? :angry::angry::angry:

 

[rob bassett]

when i got in the truck and started it up, it immediately disengaged 4wd.

clicked on and off just as it is supposed to all the way home (tested at various snowy slushy roads).

i guess the it was just a frozen actuator. hopefully that's the last time that happens. i think i'll opt to leave it in 2wd when parked overnight. i don't mind if it doesn't engage 4wd, but to have it not disengage is a serious issue.



is there anything i should look for, or do to prevent this (or just general preventative maintenance on the 4wd parts)? sorry, that's a large question i suppose.

 

[Todd Z]

Just put the truck in 4wd for a short min or 2 on rainy days....... Keeps everything moving..



Todd Z

 

[rob bassett]

well it did it again. decided to turn it on and off on a recent wet day to test it, and it worked once, then not again. (4wd engaged, then correctly disengaged, then wouldn't go back into 4wd later)

tried again later that same day, same thing. worked ok first time, but not again.

so i'm thinking the cold isn't the issue now, but something else.

methinks a trip to the dealer is in the future. (i know i know, but usual guy doesn't do the special stuff like 4wd, electronics, etc)

so to recap, when it works, the module clicks and the lights light up properly. when it doesn't work, there's no click and no light, so it never goes into the selected mode.

where to start? motor or module?

also, the truck is just about due for a new battery. starts ok, but much less oomph than usual.

several people on this and other threads suggested that electrical modifications/problems can cause funny things with the 4wd module. would a near-failing battery be a possible cause?

 

[rob bassett]

update- i replaced the 4wd module and it's been working fine.

thanks guys. (and thanks to Torrie at Fast Parts Network dot com)