Transmission Fluid Temperature Sensor A Circuit High Input
Common Symptoms
- Check Engine Light or Transmission warning light illuminated
- Transmission stuck in one gear or limp mode active
- Harsh or delayed shifting
- Transmission fails to shift out of lower gears
- Speedometer or gear indicator displays erratically
- Increased transmission temperature due to lack of proper cooling strategy
Most Likely Root Causes
- Damaged or shorted transmission fluid temperature sensor
- Shorted or damaged wiring harness between sensor and TCM
- Corroded or damaged connector at transmission fluid temperature sensor
- Failed transmission control module
- Low transmission fluid level causing sensor exposure to air
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Component Location
The transmission fluid temperature sensor is typically mounted inside or on the side of the transmission case, often near the valve body or pan.
Manufacturer Notes
Some manufacturers use this code to indicate sensor voltage above normal operating range which may trigger immediate limp mode for transmission protection.
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