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I'm not convinced the gearbox itself is in limp mode. Sounds like the transfer motor (and/or ECU) is the problem.
Easy to check the gearbox: get up to some speed and manually shift back to 2nd or first (depending on speed), if the box reacts it's not in limp.
I'm wondering if unplugging the transfer ECU is enough to default to high range, so the autobox shifts normally again. It takes the range signal only from the transfer ECU (same line as the BECM), not from any other switches.
One other thing to try is let the motor go to high while it's off the transfer box. But I fear the position switches in the motor gearbox are the cause, so you're unlikely to get a proper signal without opening them up. Rave does list the input for the different positions, so you could fool the transfer ECU with pigtails if need be.

Filip
 

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Discussion Starter #22
Ok, i think we are on to something. Im fairly sure the motor is the issue. I tried switching it from low to high while off the transfer case (its fun being underneath a running car on the ground) and the motor didnt move at all. That why i took it apart, to attempt to fix it. I discovered it WAS misaligned so i realigned it....but not accounting for the blue encoder potentiometer. So im assuming the motor is fairly ruined.

Now, since ill get a new one at a later date, i like what youre suggesting here.

Unplug the transfer case ECU under the driver's seat and see what it does? If i dont plan on using Low for a few months, Should i EVER plug it back in before i get a new transfer motor? Im in SoCal so i wont need 4wd Low for a quite a while.
 

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First of, you don't need the engine running to shift between low and high. Ignition on is sufficient, makes it a bit more comfortable if you're underneath. ;-)

And yes, you can leave the transfer ECU unplugged if you don't need it. I've had a spare car running like that for many years, after the ECU got fried. As said above, you do need the motor on the transfer box to make sure it can't jump out of high. I've had that happen after an emergency repair (bodge), not fun pulling over to the hard shoulder with no driver and a loaded trailer!

Filip
 

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Discussion Starter #24
UPDATE: Unplugged the trans ECU for a few days. It immediately went into limp mode and only had 3rd gear. I noticed it immediately.

Anyway, dealt with it for a few days then plugged ECU back in. No flashing lights on dash, no warnings, etc. Also might have all 4 gears back. Huh.

I havent taken it up to highway speeds yet so i havent confirmed 4th...but i will do that today.

Thanks for all the help, guys.
 

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what is the condition of your battery? have you had it tested? on p38 an under performing battery will cause trans ecu to log codes, go into limp modes, etc. basically your symptoms.
 

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If the autobox goes into limp mode, you probably unplugged that ECU, instead of the one for the transfer case. The autobox ECU is the forward one under the seat, the transfer box ECU the rear one, harder to reach.
But as that does seem to have solved the blinking lights, syou can say all is well. ;-)

Filip
 
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