P0841-p0846

catman3126

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Jul 24, 2012
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NE Oregon
I'm getting these two codes shortly after the truck is started and rand for 10 seconds, changed the pressure with with a known good one out of my running 03' seems to only have 5th gear as it will roll 70 on the lift with out shifting and no reverse. Called yah mike no reply yet. this is a valve body with the one solenoid off by itself that has the wire going to it. and the 03' I had didn't have that. I'm guessing that has something to do with this as it didn't do this in the 05' truck it came out of and the trans ran fine in the 03' I just took out. pinout different from an 03 to an 05 in the round plug?
 

Mike L.

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G solenoid valve body will work on any 5 speed trans.

Check wires 1-2-3-4-5 at TCM red connector.
1=grnd
2=12V
3=12v
4=12v
5=grnd
 
Last edited:

Cougar281

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Sep 11, 2006
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St Louis, MO
Except for the addition of the G Solenoid wire at position R, the pinout of the 03 main connector and 05 main connector are the same. The PSM is labeled differently in the schematics (TFT/REV/C/B/A on the 03 and TFT/REV/E/D/C on the 05 - might be just schematic labeling and they are exactly the same).

P0841 - Transmission Fluid Pressure Sensor / Switch A Circuit Range Performance
P0846 - Transmission Fluid Pressure Sensor / Switch B Circuit Range/Performance

What exactly was changed? Whole trans? Valve body? If the VB was removed, perhaps the O-Rings for those sensors aren't where they belong? Assuming everything was fine and only the VB or trans was changed, the problem is probably internal to the trans. Maybe bad PSM or like I suggested, O-Rings.
 

catman3126

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Jul 24, 2012
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Well it had power to the pins like it should. there was only 4 in the connector on this year there is not pin at # my book said it was the gray connector so now what?
 

catman3126

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Jul 24, 2012
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O-rings are fine, whole trans was swapped in with a valve body change also. when I check continuity tot eh two pins to ground its not constant it just beeps intermittently, where as is supposed to give a constant tone for continuity. maybe a ground issue. had to move it off the lift for another rig but I'll get back to it soon.
 

catman3126

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Jul 24, 2012
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Back to this truck, flashed in a stock 03' Allison known good file, truck ran and shifted fine till it started to warm up, it was doing lockup like it should everything. after it warmed to 130 deg or so it popped up a p0845 code and no shifting right. This is the built trans by me in my 03 lb7
 

Mike L.

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Switch the D and E solenoids ( 2 smaller solenoids between the F trim and B trim ) and see if the code changes to the E solenoid. This will let you know if you have a weak D solenoid as they will act up when hot.
 

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
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NE Oregon
Switch the D and E solenoids ( 2 smaller solenoids between the F trim and B trim ) and see if the code changes to the E solenoid. This will let you know if you have a weak D solenoid as they will act up when hot.


Will do thanks.
 

catman3126

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Jul 24, 2012
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Finally got back on this and swapped the solenoids and still threw the p0845 code, so I'm guessing the solenoid is find but the spool is sticking for that one?
 

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
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NE Oregon
Other than that it shifts great till it throws this code and then it is unlocked and stuck in 3rd i believe.