my 1990 ford ranger 2.9liter 4x4 does not enguage when i push the button. It dosent even do anything not a sound or click. The lights on the switch work like when i start the truck but when i try to enguage it nothing happens, i took the 4x4 motor out and it works fine. does anyone know what the problem is.

 

Serious Explorations has a huge write up on shift motor troubleshooting as does the Ranger Station here is one link4X4 Shift Motor Rebuild - Ford Explorer Ranger Enthusiasts Serious Explorations

 

Thanks for that site but could there be a problem with the automatic hubs. how could you tell if the driveshaft would be spinning.

 

You seem to know that the front drive is not engaging and you would be able to "feel" it engaging. The hubs are a seperate problem. When you say the 4X4 motor is fine how do you *know* it's fine? If it's fine then it should be shifting the transfer case. There may be a control module somewhere for the 4WD but I only know where it might be on an Explorer. There is a reset button (I think) on the module for the '91 Explorer. When you had the motor off did you notice the position of the transfer case? It is probably marked something like 2H, 4H, and 4L. If necessary you can turn it by hand (pliers) but be very careful not to damage the shaft. Remember that you still cannot shift to 4L unless it is in Neutral.

 

No lights, no click, not hubs. Unless your light is burnt out. If you get under it and spin the front driveshaft by hand you should be able to make the front hubs engage , remember to back up 10-15 feet in a straight line to disengage them. To sum up the shift motor thread the common problems are that the stop for the shift motor position sensor wears out and the sensor parks past wear it can be read so the computer safeties to 2whldr. The other common problem is that the circuit board traces get dirty or worn, oh and one other common is that the electric motor itself is worn (brushes) or dirty (armature). Hope that helps a bit. OH BY THE WAY , I have had to troubleshoot this on both my truck and a friends and while that doesn't make me a expert it puts me way the hell ahead of the average mouthy joe!

 

Do you have any idea where the curciut board is to clean it.

 

If you simply read the article in the link I sent you it will all become clear, when you take the shift motor apart you will see if it is good or not if the bumper is squished or broken. If it is intact THEN worry about the circuit board and motor brushes and stuff. OR I could come over to your place drink lots of your beer and maybe fix it ........ ....


or not