Lesson 3: powertrain – FORD FCSD TECHNICAL TRAINING FCS-14000-DL User Manual
Page 97

LESSON 3: POWERTRAIN
Monitoring The Substrate Temperature Sensor
Substrate Temperature Sensor
The TCM controls a number of high power solenoids and is surrounded by automatic transmission fluid. As a
result, the TCM can get very hot. If the temperature of the hardware rises above a predetermined temperature, the
TCM shuts down. Prior to shutting down, the TCM logs a fault code and illuminates the MIL. Following the shut
down, the transmission enters a mechanical limp-home mode. Monitoring of the substrate temperature is carried
out by a temperature-dependent resistor mounted in the processor.
2005 Expedition/Navigator New Model Technician Training
02-SEP-04
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