4l80e internal temp sensor
Thread Starter
Joined: Sep 2007
Posts: 4,188
Likes: 292
From: woodbine, md
4l80e internal temp sensor really just curious, but what was the purpose of the trans temp sensor in the 4L80E-i can read the temp with my aftermarket controller, but just curious what the orig computer did with that info-throw a code or something if it got to hot, or control something else
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Yes there is an overtemp code that set if the unit is overheated. But, most importantly the theory goes something close to this.... if we are cruising along and are reaching a max temp threshold that was programmed into the pcm, then once that threshold is exceeded the PCM will the revert to different shift schedules that are designed to not only help the tranny survive, but will also help it to stop generating heat.
In an automatic there are only two ways for it to generate heat.... the torque converter generates heat when the clutch is not applied locking the turbine to the housing. Meaning, anytime you are not locked up there is fluid shear taking place and therefore generating heat. That's why we send fluid straight out of the converter to the external cooler.
The other way it can generate heat is if an element is slipping... such as a band or a clutch pack. But, if that were happening the operator would most likely know it!
Hope that helps...
g
In an automatic there are only two ways for it to generate heat.... the torque converter generates heat when the clutch is not applied locking the turbine to the housing. Meaning, anytime you are not locked up there is fluid shear taking place and therefore generating heat. That's why we send fluid straight out of the converter to the external cooler.
The other way it can generate heat is if an element is slipping... such as a band or a clutch pack. But, if that were happening the operator would most likely know it!
Hope that helps...
g
