What it means
Drive voltage to the throttle motor is above the upper limit. Usually a short to supply or an open ground.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
The electronic throttle motor circuit supplies controlled drive to move the throttle plate. P2103 sets when the control module detects drive-circuit voltage above its expected upper limit, which can happen if a wire is shorted to supply or the motor ground path is open.
Common causes
Most likely first.
- Drive line shorted to supply
- Throttle motor ground open
- Connector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
How to diagnose it
- Record freeze-frame data and check for related throttle actuator codes to see whether the high-circuit condition occurred with other electrical faults.
- Inspect the throttle-motor wiring for chafing or contact with a power feed, and check the connector for corrosion, loose pins, or damage.
- Use the wiring diagram to check the motor ground path and its connections for an open or poor contact.
- Following the manufacturer's procedure, test the motor-drive circuit for a short to supply and verify the circuit's expected readings.
- If wiring and ground are sound, test the motor and control-module driver against the manufacturer's specification.
Common fixes
- Repair wiring shorted to a supply circuit or damaged insulation near the throttle body.
- Restore an open or poor throttle-motor ground connection.
- Clean or repair corroded or damaged connector terminals.
- Replace a motor or control module only when testing confirms that component has failed.
Can I keep driving?
Reduced-power operation or erratic throttle response can make normal traffic maneuvers difficult; avoid high-speed driving and overtaking. If the engine cannot be controlled reliably, pull over safely and arrange recovery.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.