Faulty throttle body actuator motor or binding throttle plate; Damaged or corroded wiring in the throttle actuator control circuit; Failed accelerator pedal position sensor or its connector; Engine control module (ECM) software glitch or internal driver failure; Low battery voltage or poor grounds affecting the throttle actuator circuit; Contaminated throttle body bore causing the plate to stick

DTC codes / P21xx · Fuel and air metering / P2105

P2105Throttle Actuator Control System - Forced Engine Shutdown

Q: What does code P2105 mean?

Throttle Actuator Control System - Forced Engine Shutdown. P2105 means the engine computer has commanded a forced engine shutdown because it detected a fault within the electronic throttle actuator control system. The computer monitors the throttle valve position versus the commanded position and, when it sees a critical mismatch or circuit fault, it cuts fuel and spark to prevent an unintended acceleration event.

P2105 means the engine computer has commanded a forced engine shutdown because it detected a fault within the electronic throttle actuator control system. The computer monitors the throttle valve position versus the commanded position and, when it sees a critical mismatch or circuit fault, it cuts fuel and spark to prevent an unintended acceleration event.

SystemPowertrain

Code typeGeneric (all makes)

SeverityHigh

Fix difficultyProfessional

AreaFuel and air metering

Symptoms you may notice

Engine suddenly shuts off or refuses to start, often with no warning
Electronic throttle warning light or reduced power message on the dash
Engine may idle roughly or stall immediately after starting
Accelerator pedal feels unresponsive or the engine only revs to a limited speed
Often no symptoms besides the warning light if the fault is intermittent

Common causes, most likely first

Faulty throttle body actuator motor or binding throttle plate
Damaged or corroded wiring in the throttle actuator control circuit
Failed accelerator pedal position sensor or its connector
Engine control module (ECM) software glitch or internal driver failure
Low battery voltage or poor grounds affecting the throttle actuator circuit
Contaminated throttle body bore causing the plate to stick

How to diagnose and fix it

Scan all modules for stored and pending codes, then record freeze-frame data for P2105
Inspect the throttle body for carbon buildup and clean the bore and plate with approved cleaner
Check battery voltage and ground connections at the engine and chassis
Back-probe the throttle actuator motor circuit for resistance and voltage drops while commanding the throttle with a scan tool
Test the accelerator pedal position sensor signal for smooth sweep and correct reference voltage
Perform a throttle body relearn or idle air volume learn procedure after any repair or cleaning
If wiring and sensors test good, substitute a known-good throttle body and recheck before condemning the ECM

Why P2105 is rarely just a dirty throttle body

A forced engine shutdown code often sets from a momentary voltage dip during cranking, not a failed throttle body, so always check battery health and grounds first.
Carbon buildup on the throttle plate can cause the actuator to draw excess current, and the ECM interprets that as a forced shutdown command even though the motor still works.
After replacing or cleaning the throttle body, many vehicles require a relearn procedure; skipping it can immediately reset P2105 and lead to unnecessary parts replacement.
A failing accelerator pedal sensor can set P2105 without any throttle body code because the ECM compares both signals and shuts down when they disagree.
Intermittent wiring chafing near the throttle body harness is a common hidden cause, so wiggle-test the harness while watching live throttle position data.

Can I keep driving with P2105?

Do not drive the vehicle with P2105 active because the engine can shut down without warning at any speed, creating a serious safety risk. Have the vehicle towed to a repair facility and avoid restarting it until the throttle actuator circuit is diagnosed.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.