Input/Turbine Shaft Speed Sensor A Circuit Low
Input/turbine shaft speed sensor A signal voltage below the lower limit — short to ground or open supply. Without this signal the TCM cannot calculate slip across the torque converter or first gear element.
Affected components
- Input shaft speed sensor a
- Sensor wiring
Common causes
- High likelihood: Signal wire shorted to ground
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Harness chafing through insulation
Possible symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.