My My 2006 ML 350 is still in the shop, they replaced the balance shaft and for weeks they could not get the engine light off, they replaced another gear this week and the light finally went away, they drove and tested for two days the light remained off, but when they did the diagnostic test a code p0013 came up which meant(Camshaft Position - Actuator Circuit (Bank 1). The light is still off but they say eventually it would come back on, please help its been in the shop for almost two moths with this problem.