Flickering 4wd light

[Krawfish]

I've got an 06 with 75k miles with an issue I'm tired of looking at. When I'm driving, 4wd lo and serv4wd flicker erratically on the dash. 4wd works properly, however when I shift into 4wd hi or lo, I get no lights at all. They only flicker in 2wd. I have access to a witech and DRB scan tool, so I scanned and the only code I have is "U0431 Implausible data received from FCM".

The one thing I'm suspect of is the TIPM, simply because it was changed out immediately when I bought the truck with a used, probably junkyard, non powerwagon TIPM. This might not be a problem at all, just something I've been skeptical of.

I have changed the transfer case position sensor as that seems to be a fix for many, but no dice. Also checked the adjustment on the shift linkage, all good there.

Can anyone lead me in the right direction?

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[Mule]

Wiring harnesses good on that tcase switch?
Sounds like a loose wire somewhere to me.

[OffRoadRescue]

When all my four-wheel drive and locker lights were flashing I found right behind the right front headlight in the fender is a plug with a whole bunch of yellow wires that controls everything was not plugged all the way in from the factory.

[OffRoadRescue]

When all my four-wheel drive and Locker lights were flashing I found right behind the right front headlight in the fender is a plug with a whole bunch of yellow wires that controls everything to do with the sway bar and the lockers was not plugged all the way in from the factory.

[Retired BLM Rig]

Did you use a factory transfer case position sensor or the aftermarket, mis-calibrated junk? I would focus on the TCPS.

You can test it, it should have approximately:
2H - 1172 - 1175 Ω
4H - 677 - 691 Ω
Neutral - 406 - 415 Ω
4L - 208 - 213 Ω

[Krawfish]

Wiring harnesses good on that tcase switch?
Sounds like a loose wire somewhere to me.

I'll have to give it a good look over when I can get it in the air this weekend.

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[Krawfish]

Did you use a factory transfer case position sensor or the aftermarket, mis-calibrated junk? I would focus on the TCPS.

You can test it, it should have approximately:
2H - 1172 - 1175 Ω
4H - 677 - 691 Ω
Neutral - 406 - 415 Ω
4L - 208 - 213 Ω

Admittedly I used the dorman junk. I'll have to get a OEM one and try it out.

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[Krawfish]

When all my four-wheel drive and Locker lights were flashing I found right behind the right front headlight in the fender is a plug with a whole bunch of yellow wires that controls everything to do with the sway bar and the lockers was not plugged all the way in from the factory.

I'll check for that behind mine. Thanks.

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[Retired BLM Rig]

When all my four-wheel drive and Locker lights were flashing I found right behind the right front headlight in the fender is a plug with a whole bunch of yellow wires that controls everything to do with the sway bar and the lockers was not plugged all the way in from the factory.

I'll check for that behind mine. Thanks.

That's a 4th Gen connector, you won't find it on your 3rd Gen.

Did you use a factory transfer case position sensor or the aftermarket, mis-calibrated junk? I would focus on the TCPS.

You can test it, it should have approximately:
2H - 1172 - 1175 Ω
4H - 677 - 691 Ω
Neutral - 406 - 415 Ω
4L - 208 - 213 Ω

Admittedly I used the dorman junk. I'll have to get a OEM one and try it out.

My TCPS failed the day I bought my truck from the Bureau of Land Management. I replaced it with the factory part and it lasted about 3 years and failed again, so I figured I'd try the Dorman unit. It wouldn't even work out of the box because the calibration was so far off. I had to put a 1/8" aluminum crush washer under it before it would finally work correctly. It's still working today, but I was very disappointed with the quality.

Here's a link to the thread that I posted about it: https://forum.powerwagonregistry.org/vi ... 4&p=106641

[Krawfish]

My TCPS failed the day I bought my truck from the Bureau of Land Management. I replaced it with the factory part and it lasted about 3 years and failed again, so I figured I'd try the Dorman unit. It wouldn't even work out of the box because the calibration was so far off. I had to put a 1/8" aluminum crush washer under it before it would finally work correctly. It's still working today, but I was very disappointed with the quality.

Here's a link to the thread that I posted about it: https://forum.powerwagonregistry.org/vi ... 4&p=106641

I replaced my TCPS with an oem part today and the flickering light stopped. I still get no lights in 4wd hi or lo however. I'm happy the flickering is gone, but I suspect this will cause issues with the swaybar and lockers as the truck can't "see" that it is in 4wd despite it engaging fine.

I may have to give your washer trick a try, I just don't understand why it should be necessary with an oem part. Thank you for the link to your post, I wonder if I have the issue with your throttle mapping as well