A torque converter clutch stator temperature sensor/TCC stator temperature sensor is designed to let the ECU/TCM how hot the transmission fluid is inside the torque converter. If the temperature has become too hot, the torque converter clutch operation will be inhibited and the transmission may go into limp mode, where it will be locked into a single forward gear. In this condition, a P1873 diagnostic trouble code will be stored.
How Serious is the Code?
A P1873 DTC is a very serious OBDII diagnostic trouble code, as it can signal one of two things: first of all, elevated transmission fluid temperature can result in significant damage to transmission parts like clutches, seals, and hard parts like clutch drums. If the problem does not lie with excessive transmission fluid temperature, then the TCC stator temperature sensor switch has gone bad, in which case the ECU will not allow the transmission to operate properly.
Symptoms of a P1873 include:
- Delayed gear changes
- Erratic shifts
- Lack of torque converter lockup
- Limp mode
- Transmission overheating
- Dirty transmission fluid/filter
- Damaged or corroded wiring/connectors
- Low transmission fluid level
- Failed TCC stator temperature sensor
How to Diagnose the Code?
If the transmission fluid is at an appropriate level, and there are no issues with the condition, then the wiring and connectors on the transmission wiring harness need to be inspected for signs of corrosion or damage. If no issues are found, then the torque converter clutch stator temperature switch needs to be evaluated for signs of a fault.
What Repairs Will Fix P1873?
- Change transmission fluid and filter
- Repair or replace damaged wiring and connectors
- Replace TCC stator temperature sensor
P1874: Torque Converter Clutch Stator Temperature Switch Circuit High Voltage