how to fix my vaillant turbomax plus 282/2e combi?

re: vaillant turbomax plus 282/2e combi boiler. Problem with c.h coming on when internal timer in 'off' and room stat turned down, disconnected external controls(room stat working correctly) c.h problem seemed to clear, now have intermittent d.h.w problem, cold water running out of hot taps at full flow only luke warm at a trickle, radiators getting warm at same time even when there is no demand for heating, turn on and off fault seems to clear, spindle seems to rotate on divertor valve(only checked this when all working o.k) and modulator all o.k, not sure if divertor valve sticking or faulty electronic board two faults may be connected please help.