Multiple codes and running like crap after transmission line came off

Garrettjeep06

New Member
Original poster
Joined
Jul 23, 2025
Messages
1
Location
Florida
While driving down the road the transmission line from the radiator came disconnected and antifreeze and ATFluid went everywhere. Reconnected now running like crap, throwing codes P0700, transmission control system, P0841 transmission fluid pressure sensor, and P0300, multiple cylinder misfire…
Where do I start on figuring out the problem
 
First things first, top off your fluid before you even attempt to drive it again. You could have lost a considerable amount of fluid. Once you get the fluid situation taken care of, clear the codes with an OBDII reader and reassess.

Depending on how much fluid you lost and how far you continued to drive, you could have done catastrophic damage to your transmission.
 
If you were losing both ATF and antifreeze, your transmission cooler in the radiator lost a fitting and you have probably contaminated the ATF with antifreeze which is wreaking havoc inside your transmission.
 
Last edited:
  • Like
Reactions: TJ Jim
If you were losing both ATF and antifreeze, your transmission cooler in the transmission lost a fitting and you have probably contaminated the ATF with antifreeze which is wreaking havoc inside your transmission.

This is confusing at best.

The transmission cooler is in the radiator, not the transmission. The fittings are completely distinct from one another; there is an input & output for coolant (the big rubber hoses) and then for ATF (the much smaller fittings at the bottom of the radiator). If he lost both coolant and ATF then the inner working of the radiator have spit the bit OR he coincidentally lost his tranny cooler lines and something like a radiator hose simultaneously.

@Garrettjeep06 If you did get coolant in your transmission you have a rebuild in your near future. But you also quite possibly have ATF in your coolant, which is probably also bad but maybe not the end of the world if you do a flush or something. I can tell you all about the transmission issues, somebody else will have to speak to potential cooling system/engine issue.

At the very least I would check your ATF via the dipstick and see if it was anything other than a beautiful translucent red. But I would probably actually just drop the pan and get a first hand look at your fluid, filter, etc. And then take a look at your coolant. Hopefully you aren't running a red-colored coolant, although you might be now, lol?
 
This is confusing at best.

The transmission cooler is in the radiator, not the transmission. The fittings are completely distinct from one another; there is an input & output for coolant (the big rubber hoses) and then for ATF (the much smaller fittings at the bottom of the radiator). If he lost both coolant and ATF then the inner working of the radiator have spit the bit OR he coincidentally lost his tranny cooler lines and something like a radiator hose simultaneously.

Meant to say "in the radiator" not "in the transmission". Corrected my post.
 
  • Like
Reactions: hear