No 4wd on a '98 - help!

[woodcutter500]

Hello all,

New to this forum, and I've searched for the same problem and saw a similar recent one, but thought I'd add a little more. Maybe it will help him out, too.

I have a '98 V-6 auto, ADD, Limited (more of my wife's car) with 225,000 miles. It's been a great vehicle, but all of a sudden this morning, I can't engage 4wd. I drove it the past few days in 4wd, and we've never had any problems in it's entire history.

Selecting the 4wd switch, I don't hear the normal clink/clunck (in the transfer case?) and no light on the dash. Only rear wheels spin on the ice/snow. Tried everything - in gear, moving, stopped, neutral, 4LO, turning, driving straight, driving backwards. 20amp 4wd fuse is fine. It isn't any colder than previous days, but I took it out for a 10 mile drive to warm everything up, but still no luck. I crawled under, and everything seems to be in place.

I changed all of the fluids in the car this past fall front to rear. I'm very good mechanically and a somewhat electrically. I do all of the maintenance on our 3 vehicles. So where to start?

Is the normal clink I've heard in the past the actuator, or the ADD up front? If everything is silent, should I assume that the actuator is not getting a signal, or could have failed? Could I put a meter on the terminals of the transfer actuator? If so, what should I read there? Same for ADD, maybe.

Help would be appreciated. The car is at the bottom of the hill down in front of the house until the ice melts and they're predicting another round of snow early next week.

Thanks.

 

[KellyJ]

Hello all,

New to this forum, and I've searched for the same problem and saw a similar recent one, but thought I'd add a little more. Maybe it will help him out, too.

I have a '98 V-6 auto, ADD, Limited (more of my wife's car) with 225,000 miles. It's been a great vehicle, but all of a sudden this morning, I can't engage 4wd. I drove it the past few days in 4wd, and we've never had any problems in it's entire history.

Selecting the 4wd switch, I don't hear the normal clink/clunck (in the transfer case?) and no light on the dash. Only rear wheels spin on the ice/snow. Tried everything - in gear, moving, stopped, neutral, 4LO, turning, driving straight, driving backwards. 20amp 4wd fuse is fine. It isn't any colder than previous days, but I took it out for a 10 mile drive to warm everything up, but still no luck. I crawled under, and everything seems to be in place.

I changed all of the fluids in the car this past fall front to rear. I'm very good mechanically and a somewhat electrically. I do all of the maintenance on our 3 vehicles. So where to start?

Is the normal clink I've heard in the past the actuator, or the ADD up front? If everything is silent, should I assume that the actuator is not getting a signal, or could have failed? Could I put a meter on the terminals of the transfer actuator? If so, what should I read there? Same for ADD, maybe.

Help would be appreciated. The car is at the bottom of the hill down in front of the house until the ice melts and they're predicting another round of snow early next week.

Thanks.

http://www.toyota-4runner.org/showthread.php?s=&threadid=46035


this might help

 

[woodcutter500]

Update:

The wife took the 4Runner to pick up our kid from school this afternoon, and behold, the 4wd started working again perfectly on the way home.

I still have the question: What would make this an intermittent problem? Before she left, I had her depress the 4wd selector switch while I was looking under it from the side while she was driving foward and back. The front drive shaft did not turn, telling me that it never engaged on the transfer case side (actuator). Not real sure of this system, so I don't know if the ECU is also looking at the ADD before it engages the transfer case.

Would still like some help here. A intermittent problem is almost just as bad as an all out failure.

Thanks.

 

[toytech76]

Update:

The wife took the 4Runner to pick up our kid from school this afternoon, and behold, the 4wd started working again perfectly on the way home.

I still have the question: What would make this an intermittent problem? Before she left, I had her depress the 4wd selector switch while I was looking under it from the side while she was driving foward and back. The front drive shaft did not turn, telling me that it never engaged on the transfer case side (actuator). Not real sure of this system, so I don't know if the ECU is also looking at the ADD before it engages the transfer case.

Would still like some help here. A intermittent problem is almost just as bad as an all out failure.

Thanks.

There are alot of problems with the electric 4WD systems on these things. We have repaired a ton of them. here is a basic how it works.... Pressing the button engages the actuator motor on the tcase. It drives the shift rod inside the case and uses 2 ball switches to determine its position. Once it reaches its position on the case, it turns on the front diff actuator which engages the front end. If any of the switches dont show the proper position they are suppsoed to be in, the 4WD indicator will flash until it engages properly or will stay flashing if it doesnt go in at all. Most of the time the switches in the actuator is what fails. Sometimes the internals of the actuator fail. There is a large gear with electrical contacts on it inside the actuator that needs to be clocked in a certain position to work right. If someone takes it apart and fails to clock it right when they put it back together, it wont work. Unfortunately you cant buy the switches in the actuator seperately so they make you buy the entire actuator which is super spendy. Sometimes the actuator is just sticky from not being used enough. That sounds like what your problem might be. Put it in and out of 4WD several times and do that a couple times month to keep it working right

 

[woodcutter500]

Thanks, toytech. I'll be running around in it again today. I'll keep you guys advised how things go.

Thanks again. Anyone else with thoughts please chime in.