P2640: Torque Management Feedback Signal High
The P2640 code indicates that the Engine Control Module (ECM) has detected a high voltage signal from the torque management feedback circuit. This circuit monitors the torque reduction request from the transmission control module (TCM) during shifts. A high signal suggests a short to voltage, a faulty sensor, or an internal ECM issue, potentially causing harsh shifts or reduced engine power.
01. Most Common Causes
- Short to voltage in the torque management feedback circuit
- Faulty torque management sensor or actuator
- Damaged wiring or connectors
- ECM or TCM software or hardware failure
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Harsh or delayed transmission shifts
- Reduced engine power or limp mode
- Poor fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and record freeze frame data.
Step 2: Visually inspect the wiring and connectors for damage, corrosion, or loose connections.
Step 3: Use a multimeter to check the feedback signal voltage against manufacturer specifications.
Step 4: Test the torque management sensor/actuator per service manual procedures.
Step 5: If wiring and sensor are OK, check for ECM/TCM software updates or replace the ECM/TCM.
04. Commonly Affected Makes
05. 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 or unsafe driving conditions. Limp mode may limit speed.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for diagnosis and simple wiring fixes, but sensor or ECM replacement can cost $200-$1000+.