Skip the auto shop - Our mechanics make house calls

P2100 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit Open (TACM)

Check Engine Light

P2100 code definition

Throttle Actuator Control Motor Circuit Open (TACM)

What the P2100 code means

P2100 is an OBD-II generic code which indicates that the throttle actuator control motor (TACM) circuit is open, as detected by the Engine Control Module (ECM). The throttle actuator will not work.

What causes the P2100 code?

  • The ECM does not get a correct closed throttle reading from the TACM during startup or during operation

  • The ECM puts the TACM in failure mode and closes the throttle valve if it is possible

What are the symptoms of the P2100 code?

  • The Check Engine Light will not be illuminated and the code will be set in ECM memory as a TACM fault.

  • The throttle will stay at idle and will not go above idle if the accelerator pedal is pushed.

How does a mechanic diagnose the P2100 code?

  • Scans and documents the codes in the ECM

  • Diagnoses as per the manufacturer's pinpoint test (prevents bodily damage from throttle plates closing on one’s fingers)

  • Clears the ECM code P2100 and verifies whether the code comes back

  • Monitors the throttle position sensors 1 and 2 when the accelerator is pushed to see if the TACM moves within specifications and both sensors are within specs

  • Tests and confirms the wiring and connector to the TACM to be good

Common mistakes when diagnosing the P2100 code

  • Clearing ECM memory codes before checking the freeze frame data of the failure
  • Failing to clear ECM codes after the P2100 codes are fixed
  • Moving the throttle plates by hand (causes other codes to appear in memory)

How serious is the P2100 code?

Code P2100 is an indication that the throttle cannot be opened by the actuator and the vehicle will only idle. This would make the vehicle not drivable.

What repairs can fix the P2100 code?

  • Replacing the throttle actuator assembly
  • Repairing the wiring or connection to the actuator assembly

Additional comments for consideration regarding the P2100 code

Code P2100 is the most common failure with the throttle actuator besides the actuators internal throttle plate position sensor. The actuator is replaced as an assembly. Trying to move the throttle plates by hand can cause the throttle plate to snap closed causing your fingers to get hurt.

Need help with a P2100 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: Air bag deploying

There have been many cases of defective airbags or systems causing a fault code to be stored in the system computer. If there is a fault code stored, the air bag will not deploy because the system has been shut...

Q: P0016

Hi...Diagnostic Trouble Code P0016 has many causes other than a failed camshaft position sensor. Other possible causes for Code P0016(https://www.yourmechanic.com/article/p0016-obd-ii-trouble-code-camshaft-position-a-camshaft-position-correlation-bank-1-by-jay-safford) to set include: the camshaft timing is wrong because the timing chain jumped teeth; the camshaft phaser is out of...

Q: EPC light

Any number of dozens of sensors, control modules, or computers can be causing your issue. Including the oil pressure switch being disconnected. The only way to know why exactly the light is coming on is to have the system scanned...