Throttle Actuator Control Motor Circuit Open
What does P2100 mean?
The P2100 code means the vehicle's onboard diagnostic system has detected: Throttle Actuator Control Motor Circuit Open. This is a critical severity code.
Common Symptoms
- Reduced engine power or limp mode
- Engine may not respond to accelerator pedal
- Throttle warning light on
- Engine idle only -- no acceleration
- Check engine light on
Probable Causes (Ranked by Likelihood)
- Open circuit in throttle actuator motor wiring Very High
- Faulty electronic throttle body motor High
- Disconnected throttle body connector High
- Corroded throttle body connector pins Moderate
- PCM throttle motor driver circuit failure Low
Step-by-Step Diagnostic Procedure
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Inspect throttle body electrical connector for damage, corrosion, or disconnection
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Measure throttle motor resistance across motor pins -- typical spec is 1-5 ohms
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Check for open circuits in wiring from PCM to throttle body motor -- continuity should be present
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Verify PCM is providing voltage to throttle motor pins when commanded -- should see battery voltage
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If wiring is intact and motor resistance is out of spec, replace the electronic throttle body
Frequently Asked Questions
Can I drive with code P2100?
No. The vehicle will be in severe limp mode or may not accelerate at all. The electronic throttle body cannot open without the motor circuit, so the engine will only idle. Have the vehicle towed to a repair shop.
What is a throttle actuator control motor?
Modern vehicles use an electronic throttle body (drive-by-wire) where a small electric motor opens and closes the throttle plate instead of a physical cable. The PCM controls this motor based on accelerator pedal position and other inputs.
Can I clean the electronic throttle body to fix this?
Cleaning will not fix an open circuit. This code specifically indicates an electrical problem with the motor circuit, not a mechanical sticking issue. However, if the throttle body is being replaced, cleaning the intake manifold bore is good practice.