1998 Explorer EB Won't Shift 2H-4H-4L

[mikey7]

AFTER WEEKEND UPDATES -
The Trans case (TC) is marked (I was mistaken due to bad light and eyes);
H - 9oclock
N - 6oclock
L - 12
I think this means that this eng (V6) TC (Borg Warner) combo never really has 2WD, as it's the Electromag clutch which engages (front) 4WD. If I had to put a switch on the brown wire, to control 2WD-4WD that is fine. Then I could use the 'TC shift adapter' (if I could find one cheap - junkyard ?) to shift into Hi or Low. I might never use Low anyways.

UPDATE
I had buddy in drivers seat and whil eeng running switching back and forth Auto-4high-4Low and the SM didn't move at all. I really don't care if the SM works as I would rather hook it all up with switches or levers.

UPDATE
I got the TC to shift between High-Nuetral-Low by running the engine and putting the reg tranny in N. The shift shaft is spring loaded to keep the shift forks from getting bent and taking sharp loads off i suspect.

TC CONCERN
I have noticed that the TC shifts REALLY easily, too easily. I can't imagine driving it with the Shift Motor (SM) off, or without the 'adapter kit' which I have little info on.

NO 1st or 2nd ?
Also, it seems right at the time I took off the TC SM, the regular tranny won't start out in 1 (then 2 then 3) but now starts off in 3. Could this be because of the TC's Speed Sensor I have heard about ?

WHERE is the TC's EM clutch plug (brown wire) so I can disconnect it ? Are they part of the group on the SM wires ?

 

[Mbrooks420]

It’s like talking to a wall.

 

[C420sailor]

Circling back…the truck is stuck in 4H, correct? 4x4 light illuminated, and driving characteristics are indicative of it actually being in 4H?

I don’t know how the computer feedback circuitry for the 4x4 works. I don’t know if the 4x4 indicator indicates actual position or merely commanded position.

The way I see it, you have two options.

1) Brown wire mod
2) Figure out what’s causing the uncommanded 4x4 selection. Is it the rotary switch? Is it the GEM? Other?

The truck has interlocks to inhibit shifting into low range. Transmission in neutral, 0mph, foot on brake. There may be others.

The fact that other GEM controlled electronics (wipers, etc) are not functioning properly is telling. This may be indicative of a computer issue that is causing the uncommanded selection of 4x4. This may also be what is causing the shift motor to not function.

Me? If it is in fact stuck in 4WD, I’d either brown wire it or pull the shaft temporarily so I don’t burn anything up. Next step would be to root out the electrical gremlins you have, starting with proper function of the GEM. You may need a replacement GEM—more testing is required.

I think getting rid of the shift motor is a solution looking for a problem.

 

[Mbrooks420]

You need to fix your actual electronic problems, instead of trying to bypass them, and find other ways to do this. Your transmission problems are going to be related, most likely. I can’t imagine one of these starting in 3rd without smoking the trans in extremely short order.

 

[410Fortune]

You can drive forever with no shift motor mounted to t case

The v6 trucks are control trac awd, it’s says it right on the tailgate, there is no 2wd these are awd/4hi/4low

You cannot control the t case with two relays and switches, not like the full size trucks where one relay turns the motor clockwise and the other ccw, these are different they use an encoder to adjust the motors position

The only way the dash lights come on is if the t case is physically in the gear, 4hi light only comes on w the t case in 4 hi and so on

 

[mikey7]

You can drive forever with no shift motor mounted to t case

The v6 trucks are control trac awd, it’s says it right on the tailgate, there is no 2wd these are awd/4hi/4low

You cannot control the t case with two relays and switches, not like the full size trucks where one relay turns the motor clockwise and the other ccw, these are different they use an encoder to adjust the motors position

The only way the dash lights come on is if the t case is physically in the gear, 4hi light only comes on w the t case in 4 hi and so on

Fixing the electrical problem (the COMPUTER) is not an option. Re-flashing it might be, but I'd much rather fix this using my own switches. that's all computers are, a lot of tiny switches, transistors.

Will the TC -stay- in H or L ? It seems to shift REALLY easily, and it worries me that it might slip out of gear while driving.

I wasn't going to rig up some relays to do it electronically althougjh I am a BSEE and could. I suspect there are counters or sensors and I don't want to be bothered with them. I want to shift it manually = THE KIT.

So are you saying the TC has sensors internal, so the dash lights don't get their source from the Shift motor sensors ? That would mean I can make the dash say whatever I want, just by rigging the sensors but I don't want to be bothered. I don't care what the dash lights say really.

I started a few other threads, to address some lingering issues which I hope will make the answers easier to find.

 

[mikey7]

Circling back…the truck is stuck in 4H, correct? 4x4 light illuminated, and driving characteristics are indicative of it actually being in 4H?

I don’t know how the computer feedback circuitry for the 4x4 works. I don’t know if the 4x4 indicator indicates actual position or merely commanded position.

The way I see it, you have two options.

1) Brown wire mod
2) Figure out what’s causing the uncommanded 4x4 selection. Is it the rotary switch? Is it the GEM? Other?

The truck has interlocks to inhibit shifting into low range. Transmission in neutral, 0mph, foot on brake. There may be others.

The fact that other GEM controlled electronics (wipers, etc) are not functioning properly is telling. This may be indicative of a computer issue that is causing the uncommanded selection of 4x4. This may also be what is causing the shift motor to not function.

Me? If it is in fact stuck in 4WD, I’d either brown wire it or pull the shaft temporarily so I don’t burn anything up. Next step would be to root out the electrical gremlins you have, starting with proper function of the GEM. You may need a replacement GEM—more testing is required.

I think getting rid of the shift motor is a solution looking for a problem.

Huh, I did not know that, that the TC has interlocks.

I'm about to do the brown wire mod, put a switch in circuit. But I have to go out of town for 6 days.

"pull the shaft" - you mean the F drive shaft ? I'll do the Brown Wire soon. Where does the brown wire connect to the TC though ? I'd like to disconnect it for testing.

BTW, I don't care if the windshield wipers, or anything else electrical, work. I have other 4wd's.

 

[Mbrooks420]

No one is going to tell you what you want to hear. Replacing the computer is absolutely an option, you’re just refusing to take the proper way out.

You’re doing the typical engineer shtick where you’re making everything way more difficult, and rag tag. Why reinvent the wheel? Just buy a new tire……

 

[mikey7]

You shouldn't be negative. I haven't given anyone reason to AFAIK, surely not intentional.

All I am looking for is - "there is a kit to replace the SM so you can shift the TC by hand." But if there isn't one, I can make one. Simple. 3 positions, detented or locked in place somehow, simple. My Father, God rest his soul, could make ANYthing. My Father built the 1st side-engined Supermofified race car. They're all like that now. He had to make all the parts as there were none to buy. He made a piston once for a Hodaka motorcycle we used to ride. He was IMHO, one of the best machinists there ever was. He used to make his own gears too. I was better at carb jetting though ! Dad went to Indy for 5 years IIRC, and I'll never forget the 1st year he came back, he said "you would not believe how much duct tape there is going around Indy at 200." Once Dad was making a part for his stopwatch as the winder broke when at a race. Dan Gurney said to Dad "I want to see that when you're done".

Again - reflash or another computer is not an option. I will not throw good money after bad.,

 

[Mbrooks420]

You’ve ignored all suggestions, and basically had to prove yourself what I told you from the very beginning, and then after you figure it all out, finally, you post it like a revelation.

I see zero point in dicking with Jerry rigging it all up to only have a truck that can’t move under its own power due to being stuck in 3rd. Your transfer case is the least of your worries. You can disable the transfer case. You can’t enable the transmission electronics.

 

[C420sailor]

Short version, the brown wire provides power to the front shaft clutch, which gives you 4WD. The brown wire mod installs a switch that interrupts the signal to the clutch. This allows for some pretty cool gear/wheel combinations, plus true 2WD.

It sounds to me like the shift motor is similar to a stepper motor. You’re not going to cook something up that’s going to provide the proper signal to the motor.

You’ll need to figure out a way to mechanically lock the TC in high or low range, or just hope it stays put.

Best of luck.

 

[410Fortune]

Transfer case will not jump out of 2wd, 4hi or 4 low
It will stay where you put it for many years people have shifted these electronic shift t cases by hand, there are several variations of a manual shifter made to do just that. Many people with bad shift motors would simply use plyers

I just rebuilt another 94 explorer shift motor last week the internal bump stop deteriorated and it took me 15 minutes to have it fixed on the bench and back in the truck
My originall 1988 shift motor was rebuilt 3 times and lasted 300k miles before I finally converted to a 1354m t case

The high and low 4x4’lights come directly from the shift motor on the 1354e, there are no high and low range switches in this case and no place to plumb them in (been there done that)

You can make a manual shifter device if you wish or buy a kit, I’ve seen many contraptions over the years. However I have never run into a 91-94 truck ESOF system I could not fix rather easily by:
Bench rebuild if shift motor
Swap out bad gem module or 4x4 control module (they rarely go bad)
Bad switch
Broken wire or connection
Blow fuses

Never once when shifting a 1354 w pliers did it ever jump from one gear to the other (with no motor mounted)

We are fully aware that the ecm is a series of switches and relays we have been around these trucks since the beginning

 

[mikey7]

That's all very good to know. THX !