P210F

Code

Generic P — Powertrain

Throttle Actuator B Control System - Forced Limited RPM

Brand: Generic

Type: P — Powertrain

Views: UK: 19 EN: 35 RU: 30

AI status

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Page language: EN

Causes

Failed throttle actuator motor (actuator B)
Open, shorted, or corroded wiring or connector to throttle actuator B
Low battery or poor charging system voltage during operation
Faulty throttle body (mechanical binding or contamination)
Faulty accelerator pedal position sensor or related sensors
Faulty powertrain control module (PCM/ECM) or software issue

Symptoms

Engine runs but RPM limited (reduced top speed / limp mode)
Reduced throttle response and power
MIL/CEL illuminated
Possible surging, stalling, or inability to accelerate
Stored freeze-frame data showing limited RPM condition

What to check

Read and record freeze-frame data and all stored DTCs with a capable scan tool
Inspect battery voltage and charging system (battery, alternator, grounds)
Visually inspect connectors, pins and wiring at throttle body and ECM
Check fuses and relays related to throttle/ECM power
Compare commanded throttle position vs actual position with scan tool
Measure actuator motor resistance and compare to spec

Signal parameters

Actuator supply voltage: ~12 V (key on / running)
Actuator ground continuity: low ohms to chassis/ECM ground
Control signal: PWM duty cycle/frequency from ECM to actuator (varies by manufacturer)
Actuator current draw: within manufacturer specified range (amps)
Throttle plate position sensor voltage: typically 0.5–4.5 V range
Accelerator pedal position sensor voltages: two sensors with redundant signals

Diagnostic algorithm

Connect a professional scan tool; record all stored codes and freeze-frame data. Attempt to re-run the fault if safe.
Verify battery voltage is within specification (12.4–14.8 V) while cranking and under load. Recharge or replace battery if low.
Visually inspect throttle body harness, connector and ECM connector for corrosion, bent pins, damaged insulation, or water intrusion. Repair as needed.
Check related fuses/relays for continuity and correct operation. Replace any blown/faulty items.
With ignition on and engine off, measure resistance of throttle actuator B motor and compare to spec. Look for open or high resistance.
Backprobe control and power wires: verify 12 V supply, ground continuity, and presence of PWM control signal from ECM using a scope or oscilloscope-capable scan tool.
Compare commanded throttle plate position to actual position in live data while commanding throttle via scan tool (if supported). Note any lag or non-response.
Inspect throttle plate for carbon build-up or mechanical binding; clean or service throttle body if binding is present.
If wiring and actuator tests are good, consider replacing the throttle actuator (or entire throttle body if integral) and retest.
If replacement does not clear the fault, update ECM software per manufacturer TSBs and consider ECM replacement after confirmed bench/test evidence.
After repair, clear codes and perform road test to verify fault does not return; re-check freeze-frame and readiness monitors.

Likely causes

Corroded/loose connector at throttle actuator B
Damaged harness (pinch, chafe) on actuator control wires
Actuator motor windings open or high resistance
Throttle plate binding from carbon build-up
Insufficient battery voltage under load or poor ground
ECM output driver fault or degraded PWM signal

Fault status

⚠️ Status

PCM detected Throttle Actuator B control fault and invoked forced limited RPM (limp mode) to protect the vehicle. Repair required to restore full throttle control.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours