jeep stuck in limp mode 1776 code comes up

adz930

New member
im sorry for the story here but i need help ,, do you know what the problem is when the jeep is driving ( its a jeep a 2004 jeep wrangler sahara 6cyl auto 42rle overdrive trany ) fine then it seems after it warms up it puts itself in the limp mode and its stuck in second gear, once it goes in limp mode the gauges do some dancing and the oil presure moves around also, if you come to a stop fast the trany seem to make a noise like a clunk but not to loud and goes into limp mode, the jeep has been in the trails, it has 130k on the clock and has never been apart, it seem electrical but its a guess, all trany wires and plugs were checked and no open or rubing wires anywhere if you turn the key off and on to reset the computer the the jeep will be fine for a few miles,the code that comes up now is p1776 and thats it,,, the codes were checked a week ago and it said the solinoid pack was no good so it was replaced, also the valve body was inspected and cleaned but still does the same thing and now the auto shifter is not smooth and seem like its binding since it was taken appart it also might have been getting stiff before hand but i didnt realy notice ,the fluid was checked and it was in nuetral e brake on and warm , i checked it 1 month ago when the trany was fine the oil was not burnt or smelling funny and the level was right,,,,the fluid was changed just a week ago when the soliniod pack and the trany filter was replaced, it was changed because of the problem and what the code was saying was wrong, the old fluid had 50k on it but never abused all female driven miles,, now it has new fluid which i think is not the best thing for the plates and wear parts in the trany but it did the same 2nd gear limp before anything was replaced last week when it first occured , the new trans fluid is atf4,the jeep had stock 30x 9.50x 15 tires and now it has 31x10.50x15 ,, thanks for the listening, any help would be greatly appreciated ,,, thank you and have a great day
 

I hadn't heard of limp mode before, but doing some research it appears that the 42RLE will stay in 2nd gear when it sees a certain code.

Most people seem to say replace the solenoid pack and if that doesn't fix it replace the valve body.

Did you do a complete flush, or just drop the pan when you changed the fluid?
 
Typically one of the main reasons for going into limp mode, that I have been able to find, is transmission temperature. I have had similar issues with my '05. I push my transmission pretty hard with my 35's and when the transmission temp goes up it the computer will kick it into limp mode, very annoying in town.

Prior to going into limp mode, does your engine temp go just above 210? The heat from the transmission will transfer to the engine, raising the engine temp slightly as well. If your engine temp seems to go up just prior to the limp mode kicking in, I would suspect transmission over heating. Typically on the warmer days?

The solenoid is, I agree, also an additional factor. I have a irregularly acting solenoid pack and it does contribute to the overheating issue.

One of the main fixes I have been hearing about is adding an aftermarket cooler to the transmission, before it enters the radiator. Also, there is a check/flow valve prior to the radiator that can become partially plugged, it's recommended to remove this, however, one other additional mod or tune to the transmission is required if this is done. Consult a knowledgeable, trustworthy transmission shop about this. I can't remember the specifics right now.

From Jerry Bransford:
"I was reading the FSM and it appears the engine computer calculated the transmission temp to be 260 degrees or hotter when my engine was overheating so badly last month. My transmission went into a limp-home mode where it was barely shifting and after reading what the FSM says, that pretty well confirms it was really hot... actually hotter than I suspected it was.

Based on how the FSM describes how the transmission shifts at various temps, mine had reached 260 degrees last month.
eek-1.gif
What confirmed the transmission was getting too hot was that it went into a limp-home mode several times and was barely shifting when that happened. It started shifting ok again after it cooled off.

The '04 FSM says the transmission goes into an "Super Overheat Schedule" when the computer estimates the transmission to be 260 degrees or hotter which is calculated based on "torque converter slip speed, gear, engine temperature, and vehicle speed". So based on what the FSM is saying and how my transmission was shifting at its worst, my 42RLE got to over 260 degrees when the Jeep was overheating.

Per the '04 FSM...

Hot: Oil temperature at start up above 27°C (80°F)
> Goes to a Overheat schedule above 115°C (240°F)
oil temperature
> Normal operation (upshifts, kickdowns, and
coastdowns)
> Full EMCC, No PEMCC except to engage
FEMCC, except at closed throttle at speeds above
113-133 Km/h (70 - 83 MPH)
Overheat: Oil temperature above 115°C (240°F) or
engine coolant temperature above 118°C (244°F)
> Goes to a Hot below 110°C (230°F) oil temperature
or a Super Overheat above 115°C (240°F) oil
temperature
> Delayed 2-3 upshift 40-51 Km/h (25-32 MPH)
> Delayed 3-4 upshift 66-77 Km/h (41-48 MPH)
> 3rd gear FEMCC from 48-77 Km/h (30-48 MPH)
> 3rd gear PEMCC from 43-50 Km/h (27-31 MPH)
Super Overheat: Oil temperature above 127°C
(260°F)
> Goes back to a Overheat below 115°C (240°F) oil
temperature
> All a Overheat shift schedules features apply
> 2nd gear PEMCC above 35 Km/h (22 MPH)
> Above 35 Km/h (22 MPH) the torqueconverter
will not unlock unless the throttle is closed (i.e. at
80 Km/h (50 MPH) a 4th FEMCC to 3rd FEMCC
shift will be made during a part throttle kickdown
or a 4th FEMCC to 2nd PEMCC shift will
be made at wide open throttle) or if a wide open
throttle 2nd PEMCC to 1 kickdown is made."
 
I have also heard that using anything other than MOPAR parts (filter, Solenoid, Fluid, etc) can dramatically change the way the 42rle behaves and operates. Seems somewhat hard to believe, but many sources are saying do not use anything but factory parts and fluid. Too many sources are saying it for me not to believe there may be some facts behind it.
 
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