Ошибка P0796: соленоид управления давлением C работа/Stuck Off

Pressure control solenoids are current-controlled proportional valves, and what B and C mean depends on the design: on GM's clutch-to-clutch automatics they are the pressure valves of clutches 2 and 3, on GM's CVT B is primary pulley pressure and C line pressure, on Jatco CVTs B is the secondary pressure valve, on Saab's AF40 B and C are clutch valves SLC1/SLC2. P0796 means valve C is electrically fine but pressure stays too low. GM's 6-speed flags 400 rpm slip in steady fourth gear with an intrusive test (4-5-6 clutch), the 8-speed 400 rpm for 1.5 s three times (clutch 3), the 9-speed clutch 3 slip over 200 rpm for 3 s, the CVT a line pressure deviation – all after one trip. GM noted false settings on 2017 8-speeds; a 9-speed bulletin calls for clutch inspection and a new valve body. Slipping, missing upper gears and limp mode follow.