'4WD Auto' and '4WD Low' lights flash 6 times

[r37ribution]

1st off, I just recently found this site and it has renewed my excitement about my exploder. I appreciate that . I do have a few questions about some issues with my explorer I was hoping you all could help me answer. I have a '96 XLT 4.0 with 189,000 miles on it. It runs GREAT and I like to keep up with it, which brings me to my questions...

I have the 2WD, 4WD Auto, and 4WD Low option. I just recently got the tranny and xfer case completely rebuilt with a 12/12 warranty on both through Ammco. Well, I'm dangerouly approaching 12,000 miles. When I put my truck in '4WD Auto' you can hear 2 simultanous poping noises like locking hubs are engauging? (but this isn't as loud as the double poping noise that you hear when you engauge the 4WD Low) Everything seems to be normal at this point until you go any distance the 4WD Auto and 4WD Low lights will flash simultaniously 6 times about every 2-3 minutes. I also hear a great deal of low tone noise comming from the front of the vehicle (especially when turning or stopping while in a sharp turn I hear clunking) which seems abnormal to me for 4WD Auto. It almost feels like its in 4WD Low.

In 2WD I normally get some poping from the front end when I'm going over large bumps or pot holes which I believe is the half shafts (or at least it has to be since I have replaced EVERYTHING else in the front suspenstion IE. ball joints, upper control arms, bushings, front sway bar bushings, all around shocks, end links.) The wierd part is the poping doesn't normally occure while turning (in 2WD), which I thought was a characteristic of half shafts.

I have looked for a listing of 4WD error codes on the internet some, where I came up empty. I also went to a Ford service dept who couldn't tell me what the 4x4 lights flashing 6 times meant. I would like to figure out if this is a problem with the transfer case so I can get it fixed under warranty. The wierd thing is this was doing this before I got the xfer case rebuilt but I just never used 4WD Auto long enough to bring up the codes, until recently when I realized my warranty was almost up. So I'm assuming it is somthing else, but I had to take the truck back 3 times for them to get the rebuild on it right so I'm wondering if they missed something. Anyone got a list of the 4x4 error codes? I would like to have these for future reference. Any input is appreciated.

I was also wondering if the '4WD Auto' on my ride is the same as the permanent AWD option you can get? I was just curious about this for my own knowledge, not important.

 

[r37ribution]

hey anyone out there??? i need to figure out if this is somthin covered under the xfer case warranty! thanks in advance

 

[TPLYNCH]

The sequence of flashes is the code. That sequence indicates a problem with the speed sensors. Either they are dirty, not plugged in, or defective. The sounds you're describing when in Auto makes me think the 4x4 is engaged, which means the system is reading a speed differential between front and rear and locking 4x4 to compensate. Simplest fix is the speed sensors. If that's not it, the GEM probably needs to be reflashed or replaced. The GEM is what controls the engaging of the 4x4 based on info from the speed sensors.

 

[r37ribution]

Thank you very much for the great reply. So according to the 6 flashes I get this is a problem with the speed sensors...by any chance do you have a listing of the 4x4 error codes for my furture reference? that'd be great. Could the transfer case being low on fluid cause this problem too? This was suggested in While driving the 4Hi and 4Low blinks. I think the gasket on the xfer case may be leaking.

Also do you know if when the 4WD Auto actually engauges, is this just the 4WD Low kicking in? or is the gearing for 4WD Auto more like the AWD in the 5.0 only its on the fly instead of all the time? The reason I ask is because if your on the freeway in an extreme weather condion where theres a lot of snow that hasn't been salted or plowed and the rear wheels start to slip I dont think I would want the 4WD Low kicking in at 40 Mph. Just tryin to understand how the xfer case works. Thanks!

 

[Jefe]

r37ribution, Welcome.

I know you were complaining in another thread about no one answering your posts. Those of us that have been here for a few years get tired of seeing 'common' posts, and answering them each time. May I suggest doing a search on the site before posting. For instance a search for "4wd lights flashing six times" would have given you dozens of threads with similar answers.
And a search for "4wd auto engages" brought me to this thread (and there are many others) that mentions how the control trac t-case works:
http://www.explorerforum.com/forums/showthread.php?t=109401&highlight=4wd+auto+engages

 

[r37ribution]

i appreciate the link for the info on the ControlTrac, and have removed my useless post in the other thread. The only reason I asked about how the ContrlTrac works instead of searching was because we were already on the subject. In typing my last reply to this thread I simply worte what came to mind and the thought of searching never crossed. It just seemed like a sensible question.
I did in fact do a search for this issue (as noted in the origional post!) briefly before I created this thread and came up with no specific situations where the lights blinked exactly 6 times. I was hoping this would indicate a more specific problem that someone could give me a suggestion on. Really I simply wanted a listing of ALL the error codes that the 4x4 system can give. The xfer case rebuild was a pricy addition to the tranny rebuild. My warranty on the xfer case will expire in 400 miles and I was getting a little gitty about getting an answer on this subject; hence my post about no one answering my questions and my haste in posting a new thread.

I would however, like you to realize that the thread that you noticed my complaint about no replies, was the EXACT the same as mine! Posted the very next day, about this very same issue that your asking me to search for! I find your post very ironic. The very thread that you noiced me 'complaining' in, was in fact itself a 'common' post excactly the same as this one that you are now 'complaining' about, and yet I see no recomendation to 'search' in that thread. So to complain only to me about these 'common' posts doesn't seem appropriate at all. Unless you were only referring to my question about how the ControlTrac works, but your very specific example about searching for "4wd lights flashing six times" suggests otherwise. I do not at all appreciate your cirticism of this thread as I feel even now that it was completely justified. Now posting the exact same question the very next day in another thread seems like a waiste to me.

When I found this thread other, it was right on top of mine! It recieved well over 17 posts before mine recieved any. The only difference that I could see between that thread and mine was the fact that I went into as much detail as possible to describe my problem (so that I may get more accurate replies) wheras his just stated that the lights were blinking and he wanted to know if it was the xfer case. So this brought me to my frustration.

 

[TPLYNCH]

Simmer down r37ribution. Jefe wasn't raggin on you for having a common thread. It is common for posters here to view the 15 most recent posts. Depending on the time of day you posted and who's surfing at the time has a lot to do with what posts get replies when. He's just saying that if posters come upon the other thread first, chances are they will post there, then when they read yours, not answer as they already answered in a more recent one. The only reason I answered this one is because I go backwards from the oldest to the newest.... so I saw yours first! It is also common for newbies to be given the "please use the search function" talk. Many people don't realize it's there.

Sorry, I don't have list of codes for the T/F case.

To answer questions on other thread - Yes, low fluid can also cause the problem. Don't know if you can switch sensor types. Probably not as the GEM would likely have
to be recalibrated for different input. GEM recalibration is a Dealer Only fix.

 

[r37ribution]

appreciate the info bro, thank you very much

so if the newer sensors will fit it, it seems possible to update the GEM and avoid this problem in the future. i wonder if the wiring harness is the same...

perhaps replacing it with a newer one would allow the newer speed sensors to function correctly...i have read that the speed sensors have changed over the years and you need very specific model years when doing a AWD to 4WD swap. I guess the next thing i need to do is research what all functions the GEM performs...if its just the speed sensors upgrading both the speed sensors and the GEM to a newer year should work. this then would bring about several other questions such as what year were the speed sensors were updated? ill look into this.

 

[r37ribution]

update...

i just got a call from the shop who told me the electric motor was 'sticking' i dont recall if they said they replaced it. god i hope so. but he said thats why it was feeling like it was stuck in 4x4. so this electric motor varries in its position as the % power to the front wheels is updated by the computer in real time (when the rear is slipping)?

 

[TPLYNCH]

No, the shift motor is only used to switch from 2WD or Auto into 4Lo to lock the tranfercase into fulltime 4x4Lo. In auto, It is the magnetic clutch in the t/fcase that applies power to the front driveshaft in increments of 5% based on readings from the speed sensors being interpreted by the GEM. If the sensors or the GEM are miscalibrated, and the system thinks the wheels are slipping, the clutch will remain engaged (essentially 4x4 Hi mode in '97+ Explorers) and you will get popping/clunking etc caused by running 4x4 on no slippery surface.

 

[NCSUDockhand]

I had the same problem as you 2 weeks ago and it was the shift motor. Over time, carbon builds up between the brushes and the contacts inside the motor. It took me about 30 minutes to completely take it off an apart in my parking lot. Cleaned with electrical contact cleaner and the problem is gone. I'd suggest trying a search on "cleaning the shift motor." I remember there was a really good write-up.

Also, try the Ranger Station website. The best tutorial I got was there...

TRS Shift Motor Write-Up

A couple of changes that I did: First, I did not cut any wires. I did the whole thing under my truck. Second, don't break or grind off the buttons in the torx screws. You can buy a set of security torx bits for like $5.

 

[r37ribution]

um yeah i didnt get an email that said anyone replied to this so i ended up replacing the shift motor....IT DIDNT FIX IT! and yeah now i cant return it to ford, who was nice enough to give me the part for a lil more than $160/list $290+/the 4x4 still engages intermittently any other suggestions? i guess at this point its prolly the locking hubs or speed sensors?

 

[coled43]

R37,
I have the same problem with a 97 SOHC, and have been trying to follow the 2 threads that go back and forth. Did you ever change (or remove and inspect) your speed sensors. I'm also interested in your question of when the sensors were changed from the magnetic to hall effect type, but have not seen an answer. Since I have a 97, I don't have the 2WD position on the switch and I had to cut the "brown wire" to put it in 2WD. I getting ready to check/clean or replace my sensors. Winter is coming, it is actually snowing here in Wocester MA today.

 

[TPLYNCH]

r37 - I tried to tell ya it wasn't the shift motor... It's the speed sensors or the GEM causing your problems. You do not have locking hubs. Those are only 91-94 years.

 

[Jefe]

You do not have locking hubs. Those are only 91-94 years.

Yes, but he does have the vacuum disconnect. See if you're getting vacuum down to the disconnect when you put it in 4WD.

 

[r37ribution]

r37 - I tried to tell ya it wasn't the shift motor... It's the speed sensors or the GEM causing your problems. You do not have locking hubs. Those are only 91-94 years.

Yeah I didn't check back and my email didn't tell me that there was a reply to the thread so that was my bad. Aamco did say they would replace the speed sensors free of charge! I'm taking it in Wesnesday to get this repaired. They actually listened to your post about this being a problem with the speed sensors, and are ordering them for me for Wednesday. Thanks for all your help!

Yes, but he does have the vacuum disconnect. See if you're getting vacuum down to the disconnect when you put it in 4WD.

If your referring to 4WD Low, that works fine. Its just the 4WD Auto I'm having issues with...

 

[r37ribution]

UPDATE: ISSUE RESOLVED only a tranny rebuild, t-case rebuild, 4 tires, a shift motor, and 3 speed sensors later...4WD Auto now works!!!! yay!!

thats right 3 speed sensors! one on each end of the t-case and one INSIDE THE TRANNY. which seemed to be the culperate since Aamco said replacing the outside 2 by the t-case didn't fix it and thru them off till they found the 3rd one...