Help! Transmission Fault
My E60 2004 530i with 60,000 milage has transmission faulty issues. Sometimes it doesn't recognize P R N, or sometimes it doesn't recognize D, or occasionally recognize nothing. The car starts all right from cold. After driving for minutes, the transmission fault will dump out and turned into safe mode. If the whether is cold--below 5 degree celsius, the faults never comes out. Have the car diagnosed at main dealer. They told me code 5088--gear selector switch fault. However, when I diagnosed at an independent BMW specialist, I saw 11 times fault relating with valve on the diagnose machine which the specialist cleared the memory without explaining to me.
In addition, I noticed that there is noise like truck/diesel from the gear box, because I had carefully listened to the engine which sounds perfect and powerful when it is in neutral or parking stepping on the pedal.
Would it be problem with the gear box fluid problem? My understanding is bad gear box fluid caused the diesel like noise and the gear box got overheated that result EGS can not work properly. If the temperature is the issue, why there is no fault codes stating the high temperature?
Please help me. I have wasted lots of money in checking the faults and replaced the gear selector and end up with not being fixed.