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Engine Oil Temperature Sensor



Engine Oil Temperature Sensor

Sensor Stuck
This monitor checks that the engine oil temperature (EOT) sensor is not stuck at a particular value. If the engine has been off for greater than a calibrated and the engine speed is over a calibrated limit, then the EOT must change by a calibrated amount within a set time period after engine start, or a failure will be detected. If the EOT does change by equal to or greater than this threshold a normal judgement is made.

Range or Performance Failure
The monitor checks that the EOT sensor is reading a correct value when compared to other sensors on the vehicle at ignition on.

If the engine has been off for greater than a calibrated time, then the EOT sensor reading is compared to the average of the sum of the ECT sensor and AAT sensor. The EOT sensor must be within a calibrated threshold of this reading for a normal judgement to be made. If it is outside this threshold then a fault will be detected.

Range/Performance Flow Chart








If the above table does not include details of the following enabling conditions: - IAT, ECT, vehicle speed range, and time after engine start-up then the state of these parameters has no influence upon the execution of the monitor.