4X4 module questions and help request

[PanamaExpat]

So since the doc told me I had to slow down due to some health issues I have been doing the light work on my truck. It never had 4 wheel from the day I bought it. So I am going through the troubleshooting guide from the tech section and have already been through the shift motor. For some reason the previous owner put a 4x4 module out of a 98 Explorer automatic in. My truck of course is a standard. So now after finding everything that possibly seemed that could go wrong like non working dirty dash switches and checking to see if the gear positioning was set up correctly on the shift motor I have the following symptoms.

When I started the 4X4 was dead.

Now when I turn on the key and press the 4X4 button the shift motor goes all they way to the end of it's travel. It flies right past the 4 high selection and seems to go farther than 4 low. The light for 4X4 comes on on the switch as well as on the dash.

So I checked continuity of all the wires from the module to the shift motor. I have double checked that when the motor is in 2 high the logic matches that on the chart in the troubleshooting section. I tested the edge settings and backed it slightly off and verified again that it was giving the proper 2wd logic to the module.

Cleaned both sides of the plug at the transfer motor again and checked.

Pulled the module out of the truck and opened it up.

Found that the large red thermistor in the lower left corner only had one leg connected.

Reconnected it and cleaned and tinned the edge connectors for the plugs to the switch and motor. Reinstalled and tested....Same result.


So knowing what I know about electromechanical things and how logic systems function I got to thinking maybe the IC that inputs the high and low pulses to the processor in this case a 4019 has been damaged. I won't be able to tell if that is the issue until I can find one to replace it with.

So I am wondering if I have the correct 4X4 module?
If anyone else has had this same problem?
Does anyone know if running an automatic module with a manual transmission will work?

Or is there something I am overlooking completely?

 

[wildbill23c]

Hmm, could be the explorer's 4x4 module is the control trac 4x4 module which if I remember correctly was 2WD, 4WD Auto, 4WD High, 4WD Low. Could be that with the module of this type it won't work in a ranger. I'd definitely try a different module before going any farther.

 

[PanamaExpat]

That would suck... Unfortunately I would have to get one there and have it shipped here. Then if that isn't it I would have another module laying around forever.

Anyone know any way to identify the modules?

 

[wildbill23c]

Most likely different part numbers. Not sure what the difference would be other than that, my B2 has manual everything LOL.

I'd try searching google for the part numbers and see if there's a difference that way so you know what to get.

 

[wildbill23c]

Ok, so the explorer Part Number is F87B-14B205-CF

The Ranger/Mazda/Bronco 2 Part Number is F1TB-7E453-AA.

I don't think it matters if its the automatic or manual transmission, just the explorer part number would most likely reference the control trac 4WD system and would probably be causing the shift motor to attempt to shift into a position that isn't in the transfer case of your B4000.

 

[adsm08]

I don't think it matters if its the automatic or manual transmission, just the explorer part number would most likely reference the control trac 4WD system and would probably be causing the shift motor to attempt to shift into a position that isn't in the transfer case of your B4000.

That's not it.

The 4x4 motor is not a stepper motor, but it is supposed to stop when it hits the 4HI position if the motor is on or not. IIRC it is a timed pulse. The timer is in the module, so either way I think you are probably looking at a module issue.

 

[PanamaExpat]

That would make sense. But I have no way of identifying the module other than what is written on it in the first pic. I was all excited when I finally got some life out of the shift motor.

 

[PanamaExpat]

Thanks adsm.. I was hoping you would see this. The 4019 IC chip is a quad AND/OR select gate. It would be the chip that would read the pulses coming off the wipers on the gear and pass them off to the processor. If it were bad then the processor would not receive the input. So it would not know when to stop. I should be able to grab one at one of the Chinese electronic shops here in town. It is a fairly common chip and should cost about a dollar.

I suppose one of the relays on the board could also be stuck. I'll check those out tomorrow.

You wouldn't happen to have a known good one you would part with by any chance?

 

[wildbill23c]

That's not it.

The 4x4 motor is not a stepper motor, but it is supposed to stop when it hits the 4HI position if the motor is on or not. IIRC it is a timed pulse. The timer is in the module, so either way I think you are probably looking at a module issue.

adsm08: Once again your knowledge of this stuff makes sense. So if that motor doesn't have the proper time circuitry it will just kind of do whatever it feels like then, and in this case go completely past 4Lo even. Interesting to know. I figured it was partly due to being the wrong module, course it could be timed wrong, but it should still at least stop at some position in the transfer case LOL.