TSB:HCU/TCU UPGRADE ? FOR 100 MESH SOLENOID EQUIPPED HYBRID TRANSMISSIONS - This bulletin provides information related to a software upgrade of the Hybrid Control Unit (HCU) and the Transmission Control Unit (TCU) of some 2011~2016MY Optima Hybrid (TF HEV) after replacement of the transmission with improved 100 mesh solenoids has taken place. To apply the improved logic, the HCU/TCU should be reprogrammed using the GDS/KDS download, as described in this bulletin.
