P2766: Input/Turbine Speed Sensor Circuit Range/Performance
The P2766 code indicates that the transmission control module (TCM) has detected an input/turbine speed sensor signal that is outside the expected range or performance parameters. This sensor monitors the rotational speed of the torque converter turbine, which is critical for proper transmission shift timing and torque converter clutch operation. A faulty sensor, wiring issues, or internal transmission problems can trigger this code.
1. Most Common Causes
- Faulty or worn input/turbine speed sensor 'B'
- Sensor circuit wiring open, shorted to ground, or shorted to voltage
- Corroded, loose, or moisture-contaminated sensor connector
- Damaged, worn, or missing teeth on the reluctor or tone ring
- Internal TCM failure (less common)
- Mechanical transmission issues affecting rotation of the monitored component
- Electromagnetic interference in the sensor wiring
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Erratic or harsh shifting
- Transmission slipping or delayed engagement
- Reduced fuel economy
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and record freeze frame data.
Step 2: Inspect transmission fluid level and condition.
Step 3: Visually check wiring and connectors for damage or corrosion.
Step 4: Test sensor resistance and signal output with a multimeter.
Step 5: Compare sensor readings to manufacturer specifications.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause transmission damage. Limited driving to a repair shop is acceptable if shifting is still smooth.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts and labor. Sensor replacement is usually $50-$150, but additional diagnostics may increase cost.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.