What Does P2639 Mean?
The torque management feedback signal 'A' voltage is below the minimum acceptable threshold. The ECM has detected a low voltage condition on the circuit that monitors actual engine torque output for powertrain control functions.
Common Causes
30%
Short to ground in torque feedback signal wiring or connector
25%
Failed torque sensor or position sensor with low output
20%
Poor ground connection at sensor or control module
15%
Damaged accelerator pedal position sensor circuit
10%
ECM internal circuit failure or damaged input pin
Diagnostic Steps
1
Step 1: Inspect wiring harness and connectors for the torque feedback circuit for damage, chafing, or corrosion
2
Step 2: Measure signal voltage at the sensor and at the ECM connector to isolate the fault location
3
Step 3: Check all ground connections related to torque management sensors for resistance and integrity
4
Step 4: Test sensor output voltage throughout its operating range and compare to specifications
5
Step 5: Check for short to ground in the signal circuit by measuring resistance with sensor disconnected
Estimated Repair Cost
$120 - $750
Parts + labor, varies by vehicle and location
The torque management feedback signal 'A' voltage is below the minimum acceptable threshold. The ECM has detected a low voltage condition on the circuit that monitors actual engine torque output for powertrain control functions.
The most common cause of P2639 (Torque Management Feedback Signal "A" Low) is: Short to ground in torque feedback signal wiring or connector
Typical repair costs for P2639 range from $120 to $750, depending on the vehicle, location, and whether you do it yourself or go to a shop.
May cause transmission shifting problems, reduced engine performance, or erratic throttle behavior. Vehicle is typically drivable but repair is recommended to ensure proper powertrain operation.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2639 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Powertrain Control
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
