4x4 Issue

[FurByCA]

4x4 Problem - No dash light, not working.

I've searched a bit and haven't found anything like this ... similar but not exact so here we go.

1996 4Runner SR5 4x4

When I try the 4wd, I can hear the relay - it clicks under the passenger side dash near the kick panel but there are no 4x4 lights on the dash.

4HI feels like it engages but I tested it a few times and it doesn't. I spin only the rear wheels. I try 4LO and it surges forward like it's in 4LO but still no lights (at all). If anything, my 4LO is intermittent but the 4HI doesn't work at all.

My passenger CV boot needs to be repacked or the axle replaced since it's making the clicking sounds but ... any thoughts?

Thank you.

 

[FurByCA]

bump

 

[rolling7high]

Check all the vacuum hose. The vacuum hose get old, brittle, and can leak/break. Next, check the vsv vacuum switching valve on the driver side wheel well under the hood. Lastly, if the 4x4 light is not illuminating in the dash, it is not getting an electrical signal from the front differential. Check the ADD Actuator.

The symptoms you described are similar to what my 4runner had this time last year. I checked the hoses and ended up replacing the vsv vacuum switch valve and the ADD actuator was unplugged. I went to the junk yard and found two vsv vacuum switch valves off a 2nd gen 4runner for $20 and used one. I grabbed two hoping one would work and now I have a spare.

 

[TheDurk]

J-shift or push button?

If you searched, you should have found this:

VSV’s/ADD
Don't guess at it, troubleshoot! Start at the twin VSV's (Vacuum Switching Valves) on the driver fender wall. There are two long vacuum hoses that come up from the diff, one goes to each VSV. Check to see that one of the two hose nipples on the VSV’s has vacuum (engine running, 4WD NOT engaged. If no vacuum either side, check the check valve going to the intake manifold and look for loose hoses or a hole in the reservoir. If there is vacuum going to one hose, then put it in 4WD. See if the vacuum switches to the other hose. If it does, and no 4WD, problem is the diff actuator or the line to the diff. If it does not, then just switch the hoses and you should go into 4WD. This confirms diff is okay. (Mark the hoses first so you know which belongs where!)

OK, switch them back. Then use a test light to see if electrical signal from the TC also switches sides of the VSV. If it does not, problem is the TC, the switch on the TC, or the TC actuator, or its wiring back to the button (last two for non-J shift only). If it does, but the vacuum does not, the problem is the VSV itself.

I start troubleshooting at the VSV's because you can figure out where the trouble is without having to climb under the truck. [None of this applies to '01-'02 which have an electric actuator.]

 

[FurByCA]

J-shift or push button?

If you searched, you should have found this:

J handle, I didn't see that one but I read all of this post from years ago. Similar issue but not exact.

http://www.toyota-4runner.org/3rd-gen-t4rs/70372-4-wheel-drive-problem-4wd.html

I'll trouble shoot those, thanks!

 

[Asaspades93]

I had the same problem and it turned out to be a bad vsv. If that happens to be your problem, go to a junkyard and look for a used one. I pulled one out of a 95, had to switch the bracket to mount it correctly.
Good luck, hope it's a simple fix

 

[FurByCA]

I had the same problem and it turned out to be a bad vsv. If that happens to be your problem, go to a junkyard and look for a used one. I pulled one out of a 95, had to switch the bracket to mount it correctly.
Good luck, hope it's a simple fix

Thanks - Did the bad VSV on yours cause your light to not turn on also?

 

[Asaspades93]

[MENTION=101928]FurByCA[/MENTION]
yea, the front drive shaft would engage but the axles wouldn't lock and no light.
http://www.toyota-4runner.org/3rd-gen-t4rs/134550-will-95-vsv-solenoid-work-96-a.html here is my post about it
I don't think that it is a common part that people look for in a junkyard so start there and hopefully that solves it. I paid less than 7 dollars for it

 

[Grenvilleter]

The spst ball type contact switches located on the transfer case/transmission are a real source of problems. It seems if they are not exercised regularly, the ball will oxidize slightly and fail to make positive contact hence not allowing the system to work as designed.

After you prove the integrity of your front axle, ( applying vacuum to one of the VSV hoses going to the front diff and listening for the engagement),
you can remove the contact switches from the transfer case and give the contact ball a good cleaning.

I think there are 3 of these switches located on the xmission/transfer case.
One has to be accessed by going through the hole in the floor where the shift lever comes through located on the top of the transmission and the other 2 can be accessed from underneath. They just screw out.