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Discussion Starter #1
Hello,

I have been working on this for quite some time now. A few months ago while driving home my car 2004 745Li shifted hard and went into Failsafe. Now usually i could just turn the car off and back on and it would clear out. This time it did not clear out and I had to tow the car home. Took it to a friends trans shop and it had codes in the transmission and we dropped the pan and the trans was all burnt up....So we replaced the transmission with a used one from a 745li that was running, also changed fluid and filter. When we went to start the car it is still in Transmission Failsafe and the range selector is just blinking. Hooked up the euro scan tool and cleared the trans codes but the car is still suck in Transmission Failsafe and I will not move. I am stuck and looking for any guidance here.
Car will start up and battery is new and i have programed the battery to the car so it matches and trans fluid is full and the correct fluid as well. Connector looks good and connects good too.

Thanks you
 

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After clearing the faults what faults returned? Are you having any issues communicating with the EGS? When the transmission was replaced did they notice any fluid on the connector? I have seen fluid leak through the Mechatronics electrical pins and the fluid will then push through the wire.
 

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Discussion Starter #3 (Edited)
Hello, it had code 4E23 before the old trans was removed and the connector did look to be leaking, the old trans showed signs of leakage under the connector. Once the new trans was installed the same code is still present and will not clear.
So something strange, if i clear the code with key on engine off it will clear and all is well, as soon as i start the car up it instantly goes into trans failsafe again and the code comes back. I also used the scan tool to see the PID/Active live test data and the shifter is giving the command and showing on the scan tool that it is giving the command so i am assuming it is communicating.
 

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I'm not sure what level your experience is but I would begin with checking the fuses and doing an entire vehicle scan. I would specifically look for communication faults in any module but be sure to note every fault that is present, it could possible be useful. During the scan also note if modules that are present in the vehicle are communicating with the scan tool. Diagnosing the cause of failure can often be narrowed down by reviewing faults in other systems. Just to verify the vehicle does currently start, correct? I'm gathering it just will not go into gear and the indicator on the cluster is just flashing.
 

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Hi guys.I'm new here.Mike from England.About this topic,it's a little bit late,but maybe someone need to here this,with"TRANS FAILSAFE PROG" i had it to do one thing:after was on dash 3-4 days in continue this rubbish error+airbag light on,i ended to replace the ignition switch and booom,everything back to normal!Maybe it's a good ideea to start with this when you have that problem
 
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