Hi guys- Sorry in advance for a long post about my 4wd blinking orange light problem...
I've been reading many posts on this wonderful site as well as others devoted to toyota trucks as I've got the blinking orange light - 4wd problem as well on my 2002 Sequoia SR5 that I've owned since buying it 8 years ago next month brand new - 79,000 miles on it. I am trying to avoid opening up my wallet for the dealer if I can fix it myself with parts.
I'll give you what I've done and figured so far and ask you guys to chime in with advice to nailing down the solution.
So this past summer I engaged 4wd - first time since the winter before - to get out of a slick muddy driveway and the orange light began blinking - and i had trouble getting out - now realizing i wasn't in 4wd. the 4 green lights were on but the orange was bliniking and has continued to blink since June - though I have been in 2wd all the way. I normally only put the truck in 4wd each winter - NOW I KNOW TO EXERCISE THE THING MORE!
So we had a big snow in Dec. in Virginia and I couldn't get out of my street spot that i didn't clear because my toyota trucks always just launch out of snowed in conditions. thus i figured i had no 4hi no 4 low, no locking center diff in 4 lo L shifter position. Blinking center light - no 4wd.
This week i removed transfer case actuator cover with motor and found the elec contacts of the wheel/gear to be in about the middle of the run where they ride the tracks powered by the worm drive and motor - not all the way rotated either way. so i was able to manually rotate the gear around to 4wd position and then back to 2wd position. everything felt smooth and good transfer case gear wise. at this point the drive axle going to the front diff spun freely.
after putting actuator cover back on then i put the ignition in on position and pressed the 4wd button and - i hear the buzz - but the orange light was still blinking. so i pull the cover again and the gear/wheel is in middle in 'no mans land' again. so I manually rotate it to 4wd engaging the front drive shaft and then back to 2wd freeing the front shaft.
at this point i decide to road test it and as I begin in 2wd I notice NO BLINKING ORANGE - which had been on since june. then i try to engage the 4wd hi low/locked diff, etc. forward reverse, rolling, stopped etc. - nothing. blinking orange back on - greens go on and off with switch - but only in 2wd.
i pull the transfer acuator cover with motor take it in to the bench and put 12vdc to it and get it to spin fine - so it seems like motor is o.k.
The front ADD I can't take the cover off because the phillips screw heads are rusted and don't grip at such a long reach - and though I was able to break the 4 12mm bolts free with PB Blaster I realized that I would drain the differential fluid if I pulled the whole assembly - so i held off on that so far. I think i will try to put 12vdc to the front actuator and see if i can get it to 'actuate'. so far i haven't heard any noises coming from it - but it could be not getting a signal to actuate due to the incomplete shift of the transfer actuator and a faulty position switch maybe?
so is it possible that one of the position switches is bad - sending the wrong signal or no signal to the 4wd ECU which in turn will not activate the 4wd through the front ADD?
So according to the Service Manual Diagrams that I've attached there appear to be:
5 - 4wd position switches
- No. 1 4WD Position Switch
- no.2 4wd position switch
- Transfer 4wd Position Switch on the second diagram
- and there's another one marked Transfer L4 Position switch - unless this is a repeat?
Do I simply try to unscrew each of these and test for continuity? The ADD and Transfer case sections of my service manual seem to cover removing them but not testing them.
Also - how do i get to the 4wd ecu to test it - as there is a whole table of voltages to test what's happening. Is it behind the center console?
And - is it possible that even though my transfer actuator spins and buzzes it is partially shot not having the power to go 'all the way'?
Could both actuators be bad at the same time? (I think I know the answer to this.)
I'll try to post some photos of what I'm doing as this must happen to lot's of Sequoia and Tundra owners who don't use their 4WD's regularly enough.
Any advice appreciated!