Transmission Fluid Temperature Sensor A Circuit Low Input
Common Symptoms
- Transmission fails to shift properly or remains in limp mode
- Check engine light or transmission warning light illuminated
- Harsh or delayed shifting
- Transmission may not upshift beyond second or third gear
- Poor fuel economy due to incorrect shift points
- Transmission may start in second gear
Most Likely Root Causes
- Faulty transmission fluid temperature sensor
- Damaged or shorted wiring harness to transmission temperature sensor
- Corroded or damaged connector at transmission temperature sensor
- Internal transmission control module fault
- Short to ground in sensor circuit
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Component Location
The transmission fluid temperature sensor is typically mounted internally in the transmission case or on the valve body inside the transmission pan.
Manufacturer Notes
Some manufacturers require transmission control module reprogramming after sensor replacement to ensure proper adaptive learning.
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