I may never know for sure. All lights on the 4x4 button went out, which is from the fuse. Since both trucks have mode switch trouble codes, it seems logical to start there. This was probably 5 or 6 years ago. To my surprise, it seemed to work.
The range switch is the most common problem we see with the encoder motors cause itll get bad contacts from corrosion inside and itll say indeterminate instead of 2wd,4low, or 4hi. The one for yours has the 2 connectors. I am not getting the front wheels to lock in. I am going to get mine rebuilt from…. Cheers Ran truck into snow drift recently, spent half an hour rocking back and forth in 4W-Auto while waiting for tow never revved past 2500 rpm, didn't really strain anything. When the circuit is live and the short is present, the bulb will be full brightness and hot so be sure it's not laying on the carpet or against a plastic door panel. A trouble code is also stored at that time.
If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case. I thought it should turn pretty easy. However, it requires a small harness addition, a spacer, and a new actuator. The dash-mounted transfer case mode control is a set of normally open switches that vary the voltage supplied by the transfer case module when closed. Under subsystem click on transfer case controls. There are three bolts behind the backing plate that need to be removed, after which the entire spindle should simply fall out. I recently bought a used motor with warranty and return and have not been able to get time to try it.
The button may say it's on but it might stay in two. This module should have several plugions for the wires goingt to it. With the 2 fuse out, I then plugged the other connector the one w lots of wires back in. Ussually under the driver side on the frame rail. I'm not sure that this problem is a result of that but at any rate my 4wd does not engage.
If the motor can't shift the case due to some sort of mechanical failure, it'll blow fuses. The transfer case fuse always blows. When each of the switches is depressed they will complete a circuit through their own specific resistor. My question before I find another transfer case is- could it be the actuator on the front axel? Thanks, Alex Well it's been a long time coming but I finally got around to fixing this today. If it has 12 volts, the actuator is the problem. So basically all the stuff above has been happening with the encoder motor physically off the vehicle.
Click the search button ,then the blue link. The only culprit left was the wiring harness between the fuse and front axle motor. I figured I could get by without 4x4 for the spring summer and fall then went to replace actuator motor and transfer case was cooked. In my fuse block there is only one fuse that looks like it is associated with the 4wd system. Technician should not replace any parts for this concern. The truck was going in for a recall in the steerinng pump. Since I was getting scan data and encoder motor operation, the fuse had to be good.
As far as if it actually is actuating far enough, that I don't know. The shift fork engages a spline on the passenger side of the differential, and boom! Truck has the electronic 4x4 with the auto 4wd too. When it heats, the pin in the end swells and pushes a shift fork in the front differential. I need to check some resistance values but I also tried to bench test the actuator with no success. In my fuse block there is only one fuse that looks like it is associated with the 4wd system.
Thanks, Alex since you have a short circuit to ground you will have to look over the wires to around the transfer case. I would be tempted myself to actually disconnect the battery as well and let it set for a while, maybe 30 min so the computer could soft-reset. For example the tccm never sees the tcase actually complete the shift and go into 4 low so it defaults to 2wd. Replaced actuator and encoder motor and no luck. If it has 12 volts, the actuator is the problem. I would see no problem with that! One of these has a short to ground probably.
I brought the truck home and looked at the transfer case myself. I need to know if the fuse is good now or if it just blows? A quick check of the switches did not indicate any problem with the inputs from the switch to the module while monitoring scan data. I would suggest a salvage yard try. I need you to check to make sure that the wire didn't get damaged and is touching metal. I didn't know that a truck would go that fast in 4low.
Any idea of part number? Check out the diagrams Below Please let us know what you find. The actuator is usually the problem 90% of time but recheck all of the wire harness just to maker sure there is no short before replacing any parts. So I never found out what the dealer would have done but maybe call your dealer and see what they think. I agree that the dash switches won't typically be the cause of a blown fuse. I can get it to go into low after a few tries. I would look for this especially in the engine oil. I decided to take it up the road so while in 2wd, i shifted to 4hi at low speed to make sure it worked while moving.