Transmission Fail EROOR'S

[_XS3C_]

CAN BE CAUSED BY VOLTAGE FLUCTUATIONS !


E53 X5 owners who find their battery flat (e.g. due to leaving the keys in the ignition, with an accessory running) may find their automatic transmissions in safe mode after their vehicle is jump started. When this problem manifests itself, the tranny will not change gear from 3rd.
If your BMW X5 was working fine before the battery ran flat, your problem with the transmission in safe mode is being caused by the voltage fluctuations resulting from the dead battery. Since electronic controls need a specific voltage range to work properly, improper voltages, or large swings in the car’s system voltage will result in an erroneous reading from the sensor to the control unit. Disconnecting the battery is a step in the right direction. But merely disconnecting it and reconnecting the terminals after a couple of minutes is not enough. You have to unhook the battery for at least an hour. If that solution does not resolve the failsafe problem, you can try inserting the key into the ignition and turning it to position 2. Without starting the car, floor the accelerator for a little over 2 minutes. What you are trying to do with both procedures is to reset the values in memory to their defaults.
If those DIY attempts fail, it’s time to go to a mechanic who can read trans and EGS interruption codes because there may already have been an issue with the transmission controller or its wiring even before the battery ran flat.