trouble shoot electric 4x4 2002 ranger

[mexsudo]

when I test drove it before purchase the selector sometimes worked, sometimes not.
we futzed around, got the 4x4 high, then 4x4 low... then had trouble disengaging.
after disengaging ... and checking the rest over pretty good, I pulled the trigger.

good enough, bought it and drove it home.

not wanting to chance being stuck on hard pavement far from home in engaged position I didn't try again for a few days.

Yesterday at home (I live on a gravel road) I tried again. no glory.
It's like the switch is not connected ... dash lights don't come on.

Rather than fight it I decided to ask you guys for a logical step by step of what to check.

thanks in advance.

 

[djfllmn]

do the lights come on when you first turn the key on as a self test? If not i would be suspect of the module, but i wouldn't just go throwing one in there

 

[mexsudo]

Yes, they come on for just a moment

 

[Curious Hound]

In the little gearbox on the end if the shift motor are some switch contacts that sometimes get dirty or corroded and need to be cleaned. That is one of the most common problems. Take a marker or scribe and make match marks from the cover to the body of the motor before removing the cover because the cover rotates slightly to provide adjustment.

Otherwise, this may point you in the right direction

Troubleshooting Procedure - 1995-2000 4WD Module - The Ranger Station

Is the 4WD (4x4) not working in your 1995-2000 Ford Ranger? Here's how to troubleshoot the transfer case shift control module.

www.therangerstation.com

 

[mexsudo]

Yes, they come on for just a moment

update. tried again, no lights now

 

[mexsudo]

In the little gearbox on the end if the shift motor are some switch contacts that sometimes get dirty or corroded and need to be cleaned. That is one of the most common problems. Take a marker or scribe and make match marks from the cover to the body of the motor before removing the cover because the cover rotates slightly to provide adjustment.

Otherwise, this may point you in the right direction

Troubleshooting Procedure - 1995-2000 4WD Module - The Ranger Station

Is the 4WD (4x4) not working in your 1995-2000 Ford Ranger? Here's how to troubleshoot the transfer case shift control module.

www.therangerstation.com

thanks, I will tackle that next.

 

[mexsudo]

update. tried again, no lights now

Second update. The lights come on while I am starting the car. I assume that eliminates the module...

 

[djfllmn]

not necessarily.

 

[sgtsandman]

It could be just that the contacts in the shift motor are dirty. It has been a general recommendation on here to exercise the transfer case motor at least once a month to make sure the contacts stay clean. You don't need to drive it, just cycle through the different positions every once in a while.

Since it does seem to be shifting, though slowly, it might just need to be cycled a few times to get the contacts clean again. But it might be to the point where you might need to get under the truck and physically clean them yourself.

Make sure the wires are in good condition and the connector is solidly connected and is in good condition while you are there. If all of that looks good and the contacts seem to be clean enough, the shift motor might be failing but hasn't completly failed yet.