I have an electric problem with my 745 TD 1989 overdrive. Does not switch reliably any more after about 1 hour driving. My Haynes manual did not give a complete description of the electric components. So I have started with cleaning contacts I could access and identify definitely to belong to the overdrive circuits: contacts and pushbutton in the gear switch handle and contacts on solenoid on overdrive down under the car. But shouldn´t there be still a relay somewhere giving voltage to the solenoid and to the pilot lamp at the instrument panel? Does anybody know where that relay is located, if there is one?
Thanks for any input!