error codes P0715 & P0700 came on today~PLEASE HELP

Vehicle Application: 1999 Mercedes-Benz C280 2.8L Customer Concern: Transmission will not shift, stuck in low gear. DTC P0715 - speed sensor signal. Tests/Procedures: 1. Check the fluid level using Mercedes-Benz shop tool dipstick #140 589 15 21 00. The cap lock on the dipstick tube will be destroyed when removed and must be replaced after the fluid level is corrected. Check for fluid leakage on the transmission around the electrical connector at the right front of transmission and at the shift interlock cable at the rear. 2. Use a Mercedes-Benz compatible scanner to read and clear DTC's in the Electronic Transmission Control (ETC) module and also in the Antilock Brake System (ABS)/traction systems. Also clear codes in the Powertrain Control Module (PCM). Monitor speed signals of N2 and N3 speed sensors in the ETC data stream while driving the vehicle at moderate to slow speed. If the signal drops out, or if codes reset, the speed signal is being lost from the transmission speed sensors. Potential Causes: Internal Transmission — Internal damage in the transmission resulting in a loss of signal from the speed sensors. Transmission Speed Sensor Tech Tips: A fully functional Mercedes-Benz compatible scan tool is required to read data stream on the ETC control module to monitor N2 and N3 speed sensors while driving. Diagnostic Codes: P0715

it is a straight forward job , remove the connector on the passenger side by twisting it then the female side have an 8 mm bolt in the middle hold in it, loosen the bolt and pull the outer connector straight (no twisting at this time) .empty the oil in a bucket that can hold up to 7 quarts so you can measure the oil so you add the same amount later,.after remove the oil pan,and the remove 10 star blots holding the valve body.when it is out remove the electronic part on the top and replace it with a new one . remember to align the shifter when installing. no panic easy job reset your ECU codes