P0841 & P0846 - Next steps?

FaithG

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Aug 9, 2024
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Australia
Hi everyone,

Took my TJ to the beach over the weekend, and the exit was a steep sand hill that was very cut up with lots of very deep ruts. After this, there temp gauge went to 125 degrees and the the below codes were thrown:
- P0841: Transmission fluid pressure sensor/Switch A circuit range/performance
- P0846: Transmission fluid pressure sensor/Switch B circuit range/performance

I'm now having some lagging in shifting gears, or it's not shifting at all. I've had a look at a few other threads and I think I need to do the below:
- Drop all the transmission fluid, change the filter and gasket
- Check all the wiring along the transmission
- Maybe redo the solenoid? I put a new one in in October last year, but I'm concerned I might have cooked it

Is there anything else I'm missing or that I should do? Just want to make sure I'm on the right track :)

Cheers,

Faith
 
FWIW, many people overfill the 42rle on purpose. "Being slightly overfilled can mean the difference in the transmission being able to get you up a steep climb without its ATF pickup tube sucking in air which will cause it to slip. An ATF level that works on level ground or on gentle climbs may not work for steep climbs like some Jeepers regularly do. Overfilling an automatic transmission doesn't create the same type of issues that overfilling an engine's crankcase does."
 
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FWIW, many people overfill the 42rle on purpose. "Being slightly overfilled can mean the difference in the transmission being able to get you up a steep climb without its ATF pickup tube sucking in air which will cause it to slip. An ATF level that works on level ground or on gentle climbs may not work for steep climbs like some Jeepers regularly do. Overfilling an automatic transmission doesn't create the same type of issues that overfilling an engine's crankcase does due to an engine's spinning crankshaft that would beat the oil into an airy froth."
Thank you for this! I had it overfilled prior to my trip, but I wonder if I could've had it filled further to prevent the air - When I chnage the fluid, I'll make sure she's jam-packed. How would I go about getting the air out of the ATF pickup tube?
 
Another upgrade to consider is a Black Magic Brakes transmission pan with a brazed bung for a temperature sensor, and adding a transmission cooler.

-Mac
 
Thank you for this! I had it overfilled prior to my trip, but I wonder if I could've had it filled further to prevent the air - When I chnage the fluid, I'll make sure she's jam-packed. How would I go about getting the air out of the ATF pickup tube?

it will burp itself eventually.

After this, there temp gauge went to 125 degrees
I suspect you meant 225?