4WD Problems

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FordTechOne

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Thanks. I've debated trying ForScan, but I believe it only with with Windows, right? I don't currently have that at home. I need to figure that part out, but I might just have to resort to a VM or something on a Linux box.

I think I could have more clearly communicated what I was saying. So yes, there's always a voltage on one of the harness pins, because it's tied to a hot wire. But the other harness pin (#2) is connected to the TCCM, which should toggle that pin between Hi-Z ("open") and closed, the latter of which would complete the circuit. Am I understanding this correctly?

But my problem is that pin #2 is always grounded no matter what. I'll look into this deeper after work - probably gonna see if there's continuity between ground and the pin when the truck is on, off, on with the 2H setting, on with the 4L/H setting, etc.
Yes, the TCCM will ground that circuit since it’s in 2WD. Once a 4x4 mode is engaged, the ground is removed. Since it displays “Check 4x4” won’t go into 4WD, hence why the TCCM is keeping the IWEs disengaged. Definitely get ForScan and pull DTCs.
 
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K1LDZR2

K1LDZR2

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OK, an update for anybody who might be interested.

I was able to use ForScan Lite on my AutoTechPro console in the truck. It showed a DTC of P1841 on the TCCM.

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The service manual sent me to T27 and then T28:

1708458733181.png

In my case, neither helped, but I didn't want to order a new TCCM. Since I already had an extra transfer-case motor on hand, I hooked it up just to see if it would work, and believe it or not, that fixed the whole problem! Seems like the motor itself was causing a short, or... something. Regardless, I just wanted to post an update in case anybody else had this problem.
 

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K1LDZR2

K1LDZR2

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Sweet! Not quite, but I say the phrase Linux box a couple times a week. You caught my interest lol.
I largely use Linux at home because it's free and runs better on my ancient equipment. Since most of what I do at home computer-wise is paying bills or interfacing with my ham radios, I've never upgraded from my lower-tier desktop and laptop from 2011. That lets me spend more money on trucks and guns :D
 

shigman

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I largely use Linux at home because it's free and runs better on my ancient equipment. Since most of what I do at home computer-wise is paying bills or interfacing with my ham radios, I've never upgraded from my lower-tier desktop and laptop from 2011. That lets me spend more money on trucks and guns :D
Hahaha. Yeah Linux is pretty awesome, and it doesn’t have the endless resource hogging that is windows.
 
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