TC P0934 on 2015 RAM 2500

thewrightman

Full Member
Joined
Nov 5, 2007
Messages
81
Points
6
Make
RAM
Model
2500 Big Horn
Year
2015
Miles
120000
Engine
6.7 Cummins
I'm getting the trouble code P0934 - low line pressure. I did something I don't usually do a little over a year ago; I hired someone else to fix my truck. It was just supposed to be swapping out transmissions and I had too much to do that I couldn't pay someone else to do for me. The guy I hired is very reputable and has run his own shop for a few decades. But here over a year later and three transmissions, he just can't seem to get it right. This isn't meant to be a bash session, but to get to my question i needed to give some back story. The information I find via a quick internet search is all centered around a bad sensor or connection. I don't believe that's my problem. Pretty sure the new transmission came with a new sensor and when I reset the code it doesn't always come back on immediately so probably not a bad connection. What I'm wanting to know from you guys that know more about this is what adjustments could be made to the transmission itself to cause this code?
 

billr

wrench
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Mar 12, 2007
Messages
7,932
Points
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There have been three trans replacements chasing this??? Were all three rebuilds, or any JY?

I doubt there are any adjustments, but wiring (including all connectors) and the PCM have to be suspects along with the sensor. I don't know what live-data will show regarding LP commanded or actual, but suspect there will be some clues there. You may have to use an external gauge to compare actual LP to what live-data is showing.

The fact that the code doesn't come back immediately does not mean there is no bad connection. It only means this could be the ever-popular and hard-to-find intermittent wiring fault.
 

thewrightman

Full Member
Joined
Nov 5, 2007
Messages
81
Points
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There have been three trans replacements chasing this??? Were all three rebuilds, or any JY?

I doubt there are any adjustments, but wiring (including all connectors) and the PCM have to be suspects along with the sensor. I don't know what live-data will show regarding LP commanded or actual, but suspect there will be some clues there. You may have to use an external gauge to compare actual LP to what live-data is showing.

The fact that the code doesn't come back immediately does not mean there is no bad connection. It only means this could be the ever-popular and hard-to-find intermittent wiring fault.
Thank you. This gives me some ideas to try. But to be clear, no I did not mean to imply that this had been a problem with all three transmissions. In fact it was not a problem with the 3 previous transmissions (three if you count the original). What I meant to imply was that the company rebuilding the transmissions and/or the guy installing them might be the problem. Given what you said, I'm leaning towards a bad sensor now. I'll get back to you...
 
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