Torque Management Feedback Signal B High
What it means
P2644 means the ECM saw an out-of-range high value on torque management feedback signal B — a signal used to coordinate engine torque with the transmission and traction control during shifts. It's typically a wiring, connector, or module fault. The car usually still drives, but shifts can turn harsh and it may enter reduced-power mode.
Can I keep driving? Usually drivable, but shifts may be harsh and the car can drop into reduced-power/limp mode.
Real-world scan data
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on with the code stored
- Harsh or erratic shifts
- Reduced-power or limp mode in some cases
- Traction/stability control warning light
Common causes
Most likely first
- Short to voltage in the torque-feedback signal wiringLikely
- Corroded or loose connector on the signal circuitCommon
- Fault in the module or sensor supplying the feedback signalCommon
- PCM or TCM internal faultLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and scan for related network or torque codes.
- Inspect the signal wiring and connectors for a short to power.
- Check module grounds and power supplies.
- Verify the feedback signal with a scan tool against expected values.
- Address the failing module if wiring is good. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2644?+
Can I just clear P2644?+
Related codes
Read & clear P2644 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.