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Discussion Starter · #1 ·
I was out on the trails and got into some pretty deep soupy mud. After returning to the pavement I got a P1731 (wrong gear engaged) code that put the tyranny into limp mode and won’t sift out of second gear. I have taken it to the local dealership who said that the tranny needs to be replaced. I can’t see the tranny being bad unless water was in the tranny fluid. I have dropped the pan and replaced filter and fluid with no signs of water.

I am at a loss of what to do. I have read a lot about speed sensors being a possible remedy but don’t really know where else to go. I have followed a couple of other threads that other people have ran into exact same issue but don't see any finished resolutions posted.

Hoping someone has ran into same issue and may have a good starting point for me.


Any suggestions appreciated.
 

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I think I saw the same threads you did. Someone will speak up shortly. I couldn’t find a good ”why” of it.
 

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Which year and drivetrain is this?
 

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We have a professional Jeep wrench on ROF - hopefully he can chime in. Replacing the entire tranny sounds a bit dramatic though.
 

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Was there any debris in the pan? Did you have the electrical plug off and clean it. Do you have a way to see sensor data?
 
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TBD
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Maybe disconnect every electrical connector that leads to the Tranny and give it a good spray of electrical connector cleaner. And also inspect if any wires are torn or have some of their jacket missing for a ground.
Also, is this a code you can rest with an OBDII reader?
That's the extent of my automatic expertise.
 

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Discussion Starter · #8 ·
Was there any debris in the pan? Did you have the electrical plug off and clean it. Do you have a way to see sensor data?
Fluid was clean. Magnet had some shavings but not abnormal. I don’t see any plugs underneath. Looks like the harness goes straight to the TCM which is under the dash and wasn't that deep.
 

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Discussion Starter · #9 ·
Was there any debris in the pan? Did you have the electrical plug off and clean it. Do you have a way to see sensor data?
Fluid was clean. Magnet had some shavings but not abnormal. I don’t see any plugs underneath. Looks like the harness goes straight to the TCM which is under the dash and wasn't that deep.
 

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TBD
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One other option. maybe try reseting the computer by doing the following

1. Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds. (This is to discharge the PCM capacitors, which maintain the Adaptive Memory.
2. Reconnect the Battery Cable
3. Turn Ignition Switch to the "ON" position but DO NOT start the engine
4. Turn Headlight "ON"
5. Turn Headlights "OFF"
6. Turn Ignition Key "OFF"
 

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Discussion Starter · #11 ·
Update. Got the tunner out and changed some settings and reset computer. Out of limp mode now but won’t shift into 1st gear. Takes off in second and will shift to 3rd but won’t down shift for passing gear or shift in to 1st at all.

when i drop it into 4 low it will not manually shift to any gear. Prior to these issues once in low range with an right or left switch on the shifter the D would go away and the tranny would manually shift to respective gear. This is not happening.

I have done a fair amount of research and I believe the shift solenoid is bad. Just seems weird that one drop into some soupy soup and the solenoid goes bad. Since this is an external part.

I am taking it to a performance tranny shop next week. Don’t know where else to go from here.

thanks all.
 

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Discussion Starter · #12 ·
Update. Got the tunner out and changed some settings and reset computer. Out of limp mode now but won’t shift into 1st gear. Takes off in second and will shift to 3rd but won’t down shift for passing gear or shift in to 1st at all.

when i drop it into 4 low it will not manually shift to any gear. Prior to these issues once in low range with an right or left switch on the shifter the D would go away and the tranny would manually shift to respective gear. This is not happening.

I have done a fair amount of research and I believe the shift solenoid is bad. Just seems weird that one drop into some soupy soup and the solenoid goes bad. Since this is an internal part.

I am taking it to a performance tranny shop next week. Don’t know where else to go from here.

thanks all.
 

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Transmission connector goes through the case just above the oil pan. It is a twist out style. If your tuner can read sensor data look at both your speed sensors. Not much goes wrong with these other than the occasional speed sensor.
 
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