Symptoms and Severity
In some cases, when this code is stored, it will prompt the PCM to place the transmission in “limp-in” mode. In this mode, the transmission will shift harshly. If a P2767 is presented and the transmission begins to operate erratically, the issue should be resolved as soon as possible.
Symptoms of a P2767 code may include:
- Erratic or irregular transmission shift points
- Transmission failure to shift
- Decreased fuel efficiency
- Fluctuation of the speedometer (odometer)
- Lack of operation of the speedometer (odometer)
- In some cases, when stopping, the engine may stall
Causes
Potential causes for setting this code are as follows:
- Faulty input speed sensor B
- Faulty output speed sensor B
- Damaged, worn, or broken reluctor ring or shaft
- Faulty transmission torque converter
- Loose, burned, or otherwise damaged wiring and/or connectors
- PCM failure or programming error
Diagnostic and Repair Procedures
A good starting point is always to check the technical service bulletins (TSBs) for your specific vehicle. Your issue may be a known problem with a known fix published by the manufacturer and can save you time and money during diagnosis.
A suitable diagnostic scanner, a digital volt/ohmmeter (DVOM), a system wiring diagram, and possibly an oscilloscope will be helpful in diagnosing the P2767 code.
Qualified technicians typically start with a visual inspection of the system’s wiring and connectors. Repair or replace any disconnected, corroded, burned, or short-circuited parts as necessary. Test the battery and inspect the cables and cable ends. Remove corrosion and secure the battery terminals as needed.
Connect the scanner to the diagnostic port and retrieve all stored codes. Take note of all stored codes for future reference. I also like to note the freeze frame data, if available.
If input sensor and output sensor codes are present, use the scanner’s data stream to determine the faulty circuit. Limit the data stream to include only relevant data for more responsive data delivery.
When removing the sensors, check for excessive metal debris on the magnetic contacts. Remove excessive debris before reinstalling. When the sensors are removed, inspect the interruption grooves and/or notches of the reluctor wheels. Test individual sensors using the DVOM and following the manufacturer’s specifications (found in the service manual or via AllData). Replace sensors that do not meet specifications.
Disconnect associated controllers before testing resistance and continuity with the DVOM. Failure to do so could damage the controller. Test the system circuits for shorted or open wiring. Repair or replace faulty circuits. If all system circuits and sensors are in good working order, suspect a faulty PCM or a PCM programming error.
Additional Diagnostic Notes:
- Excessive metal debris (attracted by the electromagnetic sensor) is known to cause erratic input/output speed sensor readings
- Be cautious when removing sensors from the transmission case as transmission fluid may leak from the opening
- The gap between the sensor and the reluctor is critical in some applications; ensure that mounting surfaces/threaded holes are free of any obstructions