OBD Operation Summary for 6.7L Diesel - MotorCraftService.com

Engine Coolant & Engine Oil CorrelationThe engine coolant temperature sensor reading and engine oil temperature sensor readings are tested forplausibility once per drive cycle after a long soak (8hrs or more). The values of the coolant and oil temperaturesensor readings are recorded at start up. Once it has been determined that the enable conditions have beenachieved, upper and lower thresholds are determined based on the engine-off time. The difference of the initial oiland coolant temperatures are compared to this threshold. If the lower threshold is not achieved, a fault is reported.If the lower threshold is met, but the upper threshold is not achieved and a block heater is not in use, a fault isreported. If a block heater is detected, the plausibility test does not report a fault.Figure #: ECT/EOT Plausibility Correlation Test Flow ChartFORD MOTOR COMPANY REVISION DATE: FEBRUARY 9, 2012 09.01.00.02-PAGE 88 OF 157