Automatic transmission (AT), updating the transmission control unit by flash-updating - GF27.10-P-0001-15SX

TRANSMISSION 722.9 in MODEL 204.0, 216, 221 

Shown on model 221 

Fig 1: Identifying Diagnosis Multiplexer And Data Link Connector

Courtesy of MERCEDES-BENZ USA

On transmission 722.9 the transmission software used can be exchanged for a more up-to-date version. This updating is described as flashing and is carried out using STAR DIAGNOSIS.