P2105 indicates that the powertrain control module (PCM) has detected a failure in the throttle actuator control system and has commanded a forced engine shutdown to protect the engine.
The electric motor that moves the throttle plate can seize, have worn brushes, or develop an internal short, causing the PCM to detect an abnormal condition and force a shutdown.
Open, short, or high‑resistance wiring/connectors (including damaged insulation, corrosion, or loose pins) can prevent the PCM from properly controlling the actuator.
If the sensor that tells the PCM the actual throttle position is out of range or sending erratic data, the PCM may interpret this as a system failure.
A missing or degraded fuse/relay can cut power to the actuator, triggering a forced shutdown.
Poor chassis ground or low system voltage can cause the actuator to behave erratically, prompting the PCM to shut the engine down.
An internal electronics failure within the PCM itself can produce false fault codes, but this is the least common cause and should be investigated only after other components are verified.
No. In most cases the problem lies in the throttle body, its wiring, or related sensors. PCM replacement is rarely required and should be considered only after all other components have been tested and confirmed good.
A heavily carbon‑caked throttle plate can bind the actuator, but the code is set for an electrical/system failure. Cleaning may help if the actuator can still move freely, yet the underlying fault must still be diagnosed.
Most vehicles will enter a limp‑in mode, limiting speed and throttle response, or they may not start at all. Driving is not recommended until the issue is resolved.
Re‑inspect the throttle circuit, ensuring all connectors are seated and no intermittent wiring issues exist. If the problem persists, have the vehicle professionally diagnosed for persistent electrical faults.