Originally Posted by ethorson
My 2007 CRD with the NAG1 transmission has also been "possessed" with similar symptoms. Once I got the transmission overtemp indication when I shifted into park before shutting down. At other times I get a MIL with a code of P0705 (Transmission range sensor circuit PRNDL). And then sometimes I get a "Service park assist system" message.
I think all of these problems are related to the transmission temperature sensor circuit on the NAG1 transmission. For whatever reason MB decided to share the neutral safety switch function and transmission temperature measurement on the same wire by placing the temperature sensor in series with the safety switch. If you have a bad connection in this circuit then you may get a false overtemp or you may get a false indication of neutral or park.
I suspected that the most likely spot for a connection problem would be at the transmission connector, which is near the right front corner of the transmission oil pan. I gained access to the connector be removing the skid plate and a small heat shield next to the connector. I then rotated the connector bayonet locking ring counter-clockwise to eject the connector and then reversed the process to plug it back in again. I repeated this several times with the idea that this may remove some oxide from the connector pins and restore the integrity of the connection. Note that there have been problems with the adapter on the transmission that the connector plugs into. If transmission fluid is leaking in this area or if fluid comes out when you unplug the connector then you need to have the adapter changed.
So far I have not seen any weirdness after this exorcism, but time will tell if my suspicions are correct.
Hi, just curious if you ever had issues again with starting etc after this fix?
I had the starter replaced 2 month ago but two days ago it started again. I drive to the local super market, get my groceries and when I get back it displays "Transmission over temp" and it wont start. Wait and try a number of times and it starts. Not very reliable. So today I had your "fix" done and see if I will get a possessed jeep again. Mine is a 2007 Commander. THX!