OBD Codes List

Diagnostic reference · P2551

P2551

Torque Management Request Input Signal B High

System
Speed and idle control (P code)
Lamp
Check Engine Light
Category
Powertrain - Computer and Auxiliary Controls

What it means

P2551 means Torque Management Request Input Signal B High.

Check these first

  • A short to voltage on the torque management request input B circuit
  • A failed accelerator pedal position sensor
  • A stuck throttle actuator control module
  • Chafed torque management request input B wiring

What to do next

  1. Read torque management request input B on a scan tool
  2. Test the torque management request input B circuit for a short to voltage
  3. Check the accelerator pedal position sensor signal
  4. Check the throttle actuator control module output
  5. Inspect the torque management request input B wiring for chafe
  6. Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.