..... in addition if you have a Sprint built > WF 50,001 that wire ( White / Pink ) goes to an in-line splice and appears as a "72" labelled "Alternative heater supply ". I think the idea is that the green wire from the connector local to the heater motor is disconnected and then reconnected to this "72" connector. This then gives the ability to run the heater motor with the IGN set to the AUX position.
Tony.