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4x4mike
09-08-2009, 08:35 AM
I was messing around the other day on a dirt road and decided to put the 4runner in 4WD. I did and the light did not turn on. I sat at idle for about 30 seconds, went forward and backward and nothing. I then shifted into 4lo and it went in but still no light. Honestly it's been 3-4 months since I last took it out of 2wd but I can't think of anything that could have messed it up. I also am not sure it's just a bulb as the light worked last time and it doesn't get much use.

Is there anything else I could check before I break open the dash? I don't think there is any harm in driving it with a bad bulb, right? Other than accidentially DD in 4wd. The system doesn't require the bulb to be lit, right?

mastacox
09-08-2009, 09:45 AM
I then shifted into 4lo and it went in but still no light.


Are you sure you actually shifted into 4wd-lo, or were you just in 2wd-lo? Did you test to see if the front wheels actually had power to them?

If you're not actually shifting into 4wd, you should troubleshoot the vacuum lines in the ADD system. It's possible one of the lines has cracked and is preventing the ADD system from engaging.

Seanz0rz
09-08-2009, 10:07 AM
if that was the case wouldnt the light flash?

mastacox
09-08-2009, 10:21 AM
I'm not sure if the 4wd light flashes when it's trying to engage, mine is only on or off. But I've never had problems with the ADD system on this 4Runner either.

L33T35T Tacoma
09-08-2009, 10:29 AM
Does the light light up when you first turn the key to on? does it normally?

4x4mike
09-08-2009, 12:03 PM
To my knowledge the light never turns on when the key in first inserted and the other lights turn on.

I did get stopped up in some rock in 2wd. I shifted to 4hi, went back a little then forward and got out of it. I'm pretty sure that even with a lot of throttle in either direction I wouldn't have been able to get out. I can not verify the same with 4lo and the 2lo comment. I guess I could throw the thing on jack stands and start shifting and gassing it but I'm not sure it would be one of the safeest things I've done.

Seanz0rz
09-08-2009, 12:46 PM
while in park, or parking brake set, turn on the truck, shift into 4wd. get under and see if you can turn the dshaft by hand. if you cant that means either the front diff has actuated or the tcase has, or both. now raise the front tires off the ground and see if you can turn one without turning the other. if you cant, that means the whole system is working. if one turns but not the other, it means the front diff is not actuating.

4x4mike
09-08-2009, 01:43 PM
Cool, I'll try this when I get home. I did put it in and out at the home depot parking lot and then decided to go in to do my shopping. I went about 200 feet and tried to turn into a parking spot and and I couldn't. The steering was all tight (guess it was still in 4lo) so I stopped (I had already shifted into 2hi), put it in reverse then forward again and was able to park no problem. This makes me believe that the system works but I'll try the driveshaft and lifting the front.

Seanz0rz
09-08-2009, 02:39 PM
yeah that would lead me to believe that its working and its simply an indicator problem.

4x4mike
09-08-2009, 03:03 PM
That's where I'm at right now but I wanted to make sure that the system would work even if the light was out. Another thing that gets me is why the light is out. It doesn't get a lot of use and I haven't been into the dash to mess it up. If everything works just fine I'll put the light replacement at the bottom of my to do list.


I think Bob has a write up for taking out the instument cluster.

4x4mike
09-08-2009, 05:32 PM
Ok, on the driveway with the shifter in 4hi the driveshaft doesn't move (engaged). When if shift into 2hi and go forward and back a few feet it disengages and the driveshaft will move when I turn it by hand. I'm Mr. Mom tonight so it'll be after 8 before I can jack up the front.

4x4mike
09-08-2009, 08:30 PM
Mr. Mom jacked up the front of the 4runner and found this:

When in 4hi, transmission in N and parking brake on the driveshaft does not spin by turning it with my hand. When I turn on wheel/tire the wheel/tire on the other side spins in the opposite direction. This is the case with both front wheels.

After I tried this I climbed in and put the transfer case in 2hi. I turned the driver side wheel and only it spun. Same with the passenger side tire. I climbed under and the driveshaft would spin freely in both directions by hand.

As far as I know it's all working and I may have a blown bulb. The 4wd fuse looks good so it looks like I'll be fine for Pismo.

Thanks for the advice.

reggie 00
09-08-2009, 10:17 PM
Not sure if its the same on yours, on my 90 i had a wire connected to the the ADD shifter fork that would basically light the light after it shifted the ADD sleeve.

When i forgot to put all that back in and accidently welded the ADD sleeve in place, to get my light to work i had to jumper the connector. Yours is probably the lamp like you said, but to make sure peek under the skid plate to see if that wire is plugged in. 5 min versus 1hr.

partsman93274
09-09-2009, 07:24 AM
I have a 91 4runner and when it's in 2hi I can't turn the front driveshaft by hand. I used a pry bar to gently turn the front shaft and the whole truck moved. I don't think it is shifting out of 4hi. Anyone else have this problem? Does that year have vacuum lines that I should check? I just got this vehicle and want it working in time for pismo. :headscratch:

Crinale
09-09-2009, 10:37 AM
in 2 hi the drive shaft should turn by hand on the 91's... and yes there are vacuum hoses... do you have the v6 or the 4cyl? if you have the v6 (3vz-e) its got a WHOLE MESS of vacuum hoses... i wouldnt even know where to start...

partsman93274
09-09-2009, 12:29 PM
It's a four cyl. Not a big fan of the v-6. I'll crawl under tonight and see what I find. I might put all four tires in the air and spin the rears while watching the front driveshaft.

partsman93274
09-09-2009, 08:42 PM
So I look at the vacuum lines on the axle disconnect on the front only to find that they have been gone for awhile. I put the 4runner up off all four tires and still can't move the front driveshaft without the front wheels moving. I am hoping that this means the ADD is stuck in 4WD mode and I shouldn't worry about it. I put it in 2WD and only the rear shafts when in gear so I guess it's all good. Right?