18036 - Service Update. Certain vehicles without an auto high beam option (RPO TQ5) may have been assembled with the incorrect high beam turn signal multifunction switch (TMFS). When customers press the auto high beam button on the high beam TMFS switch nothing will happen. High beams will operate if the customer push/pulls the TMFS. Dealers are to replace the TMFS, and inform the customer that their vehicle is not equipped with the auto high beam feature.