I am retired now but worked in the electronically controlled mechanical industry, and many occasional faults that kept recurring intermittently were often down to a bad connector as over time the pins would oxidise and cause a poor connection often just removing and replacing the connector would clean the terminals and cure the fault and if not a clean with switch cleaner would do the job the problem with most engineers is that they think the diagnostic computer is god and act accordingly and in the motor trade more money charged to us the customer. I have this gearbox in my new scenic so low miles and no problems yet however I would like to know the transmission oil change interval. hope this helps