T5's 4C only have Comfort/Sport mode, And R's 4C have Comfort/Sport/Advance mode. I want to upgrade my 4C control capability same with R.<p>2005 T5 have the same SUM H/W & S/W with 2005 R, And T5 have the same control line with R for 4C control pannel.<p>When I connect R 4C control pannel to my 2005 S60 T5, It's can not work.<br>I had check the signal for my car, The difference is R's SUM output is 12V, T5's SUM output is 5V. <p>Does anyone know, How to upgrade it ? Or which S/W or H/W that I need to upgrade or change it? Thanks a lot.