P2100

Throttle Actuator A Control Motor Circuit/Open

Fuel & air metering Generic OBD-II High

What it means

P2100 means the PCM detected an open in the circuit that drives the electronic throttle actuator motor. On a drive-by-wire system this motor opens and closes the throttle plate, so an open circuit usually forces the engine into a reduced-power failsafe (limp mode) where it may only idle. This is a serious drivability fault — the engine may start but won't respond normally to the pedal.

High

Can I keep driving? Drive minimally — an open throttle motor circuit usually forces limp mode with sharply reduced power, and the engine may only idle.

Real-world scan data

Seen in

1,352

scans in the past year

Found in

0.2%

of scans

0.4%

of scans that found faults

Appears alongside · share of P2100 scans

P2101in 28.7% of scans

P0122in 27.0% of scans

P0123in 22.6% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on (often with a throttle/reduced-power warning)
Limp mode / severely reduced power
Poor or no throttle response; engine may only idle
Rough idle or stalling

Common causes

Most likely first

Open or shorted wiring in the throttle actuator motor circuitLikely
Corroded or loose throttle body connectorCommon
Failed throttle actuator control motor inside the throttle bodyCommon
Carbon buildup binding the throttle plateLess often
Faulty PCM / drive-by-wire control (rare)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and inspect the throttle body connector and wiring for opens, shorts, or corrosion.
Clean the throttle body and check that the plate moves freely, then reset and re-test.
Measure the actuator motor resistance and circuit continuity against spec.
Repair damaged wiring or a bad connector; replace the throttle body if the motor is open.
Perform any required throttle relearn, clear the code, and re-test. Consider the PCM only after wiring checks out.

FAQ

Quick answers

Is it safe to drive with P2100?+

Only minimally — the throttle usually drops into a reduced-power failsafe, so limp home or tow it and repair before normal driving.

Can I just clear P2100?+

It returns immediately if the motor circuit is open; the throttle won't respond normally until the wiring or throttle body is fixed.

Read & clear P2100 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX