4wd will not work on 2004 Tacoma

hey yall,
My truck is up on a lift, I'm able to turn all four tires freely. When I'm in 4wd high my front drive shaft does not turn when I'm spinning the back wheels. Why doesn't my front driveshaft turn? Is it the transfer case actuator? Or something with my transfer with my transfer case?
Someone, please help!

 

Dear Chris,

There are a few things that could be the fault of your rig being unable to get into 4x4. At least, you know for sure since it is up in the air that you are not able to get four wheel drive to work. Both the transfer case and the actuator are likely candidates as to why your rig is not going into four wheel drive. The next thing to do while the rig is in the air is to determine if the front wheels and front gear shaft spin in four wheel drive low. Do this and then report back to us.

Good Luck,
Paul

 

TacomaJunkie8691,
At this time I have the front actuator off and the front driveshaft disconnected. When I manually lock the front axle by sliding the sleeve over, both tires do not turn, but I see the yok on the differential turning. When I turn each of the tires separately I see the differential turning that's all I can tell you. What I don't understand is why I can turn the transfer case yok too the front drive shaft easily by hand. Shouldn't it be difficult to turn? I noticed there is a spot for another sensor on the transfer case actuator and it's not there, i do not have any loose wires or a plug hanging anywhere, is there something supposed to be there? (I removed both the front and rear actuators and cleaned and put the transfer case one back on, I also changed the transfer case sensor that's mounted on the transfer case actuator.)
Thanks for getting back to me so quickly would you like pictures for a better visual?
Chris.

 

From what I'm reading you have the push button transfer case not the J shift?

I would start by checking for power going to the actuators while in 4wd with the key on in the run position. If you have power probably a bad actuator have some one engage and disengage the 4wd while you're under listening for which isn't working. If you don't have power to both check fuses and the switch on the shifter followed by checking wiring around the shifter for broken or pinched wires. If only one is getting power trace the wires back looking for broken or pinched wires.

 

Dear Chris,

Joe (Brokenbrute) has given you some good advice. Unfortunately, I am not an electrical expert or an expert on ADD four wheel drive, which is what is found in your Tacoma. Our old 1999 Tacoma has the old style four wheel drive system with manual locking hubs.

I am going to try and help you, though. Okay, so your Toyota Tacoma is a model year 2004 with ADD, and TRD, which means it has the ability to let the user lock the rear differential and the ability to let the user completely engage four wheel drive from the cabin. As a result from being equipped with these features, you have a four wheel drive computer in your truck, which means you are engaging these features through intelligence rather than ignorant relay switches. Lets hope, that the computer is not the guilty party as far as your four wheel drive dilemma. The chances of it being intelligence are pretty small.

When your rig is up in the air, and four wheel drive is not engaged, you will have the freedom of spinning the front drive shaft, and as a result, the front wheels will spin. If your entire rig is in the air including the rear, you will still be able to spin the front gear shaft in two wheel drive, and if you put it in four wheel drive and spin the front drive shaft, as a result, the rear drive shaft will spin as well as the rear wheels. Just make sure the emergency brake is off when conducting this test.

ADD stands for automatic differential disconnect. This is the four wheel drive system that is installed in your Tacoma. ADD works from the transfer case, and is engaged from the transfer case. Once the transfer case is engaged in four wheel drive, kinetic energy from the spinning drive gear in the transfer case is transferred by a chain to the front drive gear in the transfer case to engage power to the front drive shaft. This in turn engages the rig into four wheel drive mode. When your ADD system is in two wheel drive, the front drive shaft and the front wheels still spin when the rig is on the road, but there is no power from the transfer case being transferred to the front drive shaft. They are spinning because there is no release in your front differential or front axle. The front differential and front axle are permanently engaged. The actuator found on your front differential is not actually engaging the front differential or four wheel drive, it is simply monitoring the front differential for the four wheel drive computer.

Your front differential is an open style differential, which in a nut shell means the right and left side are not locked to one another. If you jack up just one side of your Tacoma, you will be ale to spin the front wheel that is in the air even though the other front wheel will be completely unable to spin.

Hope this helps Chris because this is everything I know about ADD.

Take care,
Paul

 

Thanks, Paul I think I understand that the test I'm doing with the front axle and transfer case was meaningless. It turns out when I manually slide the sleeve that the add is supposed to slide over the front axles engage properly. As far as the front diff yok turns when you turn either wheel.

With the ignition on, I pressed the button for four high, I hear the transfer case actuator engage but the front add does not move, but when I turn the ignition off then back on the front add moves into proper position. During this process, there is no 4 x 4 light indicator on the dashboard. When I press the brake and clutch and move the shift lever from four high into four low the four wheel drive light comes on and stays on. After turning the ignition off then back on the four-wheel light stays on. When I disconnect the front add the light still stays on. when I disconnect the rear actuator the 4 x 4 light blinks.
Does this indicate an issue with the T/C actuator? I already changed the transfer case sensor/switch.

The blue Plug on the side of the transmission is a grey wire and a white and black wire. I believe it is the low four-wheel-drive transfer case sensor. That plug has over 11 volts going too it, and the continuity is good, the switch works.

Why does the add only work after pressing the button then turning the ignition on and off? Is this a ground issue? shift selector button is good.

 

Thanks for the feedback brokebrute.

 

Update. I have removed and cleaned the T/C actuator 2X. And replaced the transfer case switch/sensor that is attached to the T/C actuator. The 4WD light does not come on when you press the button and the ADD does not move regardless of the Transfer case shift selector is in. However when I jump the wire to the transfer case plug attached to the T/C actuator 4WD light comes on ADD moves into position without turning off the ignition.
Question????
Why isn't the transfer case sensor/switch not closing the circuit? I thought that was a mechanical closure.

 

Hi, what do you mean by jumping the t case plug? I have the same issue im trying to figure out. When 4wd is pressed, no light and it does not lock. Tcase actuator do makes sound when pressed and the front shaft locks.

 

https://www.tacomaworld.com/threads/help-with-diagnosis-4wd-not-working.817804/

 

I have the electrical add actuator.

 

What's your issue? I'll dig through some schematics.

 

I have 04 Tacoma with push button 4WD. My 4WD works before my passenger CV axle broke couple months ago. After installing a new CV axle for both driver and passenger, my 4WD is not working. When I press, no 4x4 light, and I hear the TCase actuator spins & it actually locks the front shaft but it doesn't lock the front diff. Sometimes I hear the front actuator trying to move but its rare. Do you think I have a bad front actuato?

 

Pull the plug at the front actuator and check for 12v at the plug with the key "ON" and tcase in 4wd

 

Which pin are those to check 12v?

 

I also replaced the transfer case switch sensor.

 

Attached is the front A.D.D. inspection procedures although I'd like to start with the shifter itself since you aren't getting any indication whatsoever on the dash.