This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
P2106 is an OBD-II Code that refers to Throttle Actuator Control System Forced Limited Power
A P2106 code is a generic diagnostic trouble code that occurs when the PCM/ECM detects a major failure in a system causing the PCM to go into “limp mode” or “fail-safe mode” and limit the throttle actuator to limited power. To stop any further issues from occurring, the engine will not accelerate until the condition is resolved, including any error codes.
Common causes for this code include:
- The engine overheats
- ABS, Traction Control, or Stability Control problems
- Voltages in the system that are Abnormal
- The EGR valve may have malfunctioned
- Leakage of the coolant
- The MAF (mass air flow) is not working
- Modifications to the Drive axle
- Transmission problem
The symptoms of a P2106 code are:
- The Check Engine Light has come on
- ABS Light illuminated
- The engine will not start
- There is little or no throttle response
- The automatic gearbox will not shift
- Additional codes are present
To diagnose a P2106 DTC code, a technician would:
- Scan for codes in the ECM and look at the freeze frame data for failure.
- Check that the scan tool is calibrated and working properly.
- Check all connectors in the wiring system for corrosion, damage, or repair. Check the throttle body/accelerator pedal position sensor harness is connected properly to avoid a short circuit.
- Inspect vacuum leaks from any broken lines from the intake manifold to the PCM
- Inspect the coolant for any mixture of water and anti-freeze
- Inspect the fuel system for leaks or starvation
- Check the battery voltage to make sure it is at 12.4 Volts minimum and 28 Volts maximum .
- Check the power and ground circuits in the harness.
- Check all sensors for proper operation.
The following are some of the most common mistakes that a technician may make when diagnosing a P2106 code:
- Not properly identifying the cause of the problem when using Freeze Frame data to diagnose the P2106 code
- Not calibrating the scan tool before diagnosing the P2106 code
- Unplugging any sensors while checking for codes in order to not erase them while testing
- Testing with an unsupported or uncalibrated scan tool. Calibrate the scanner before using it.
- Checking all the PCM connections without checking the sensors that are actually related to the P2106 code
- Not checking the coolant level, mixture of water and anti-freeze, or voltage
- Testing with a stale fuel sample
- Checking only one sensor at a time instead of performing system tests where multiple components will be tested.
How serious is this?
A P2106 code is considered to be an engine code that means that the issue is still potentially causing further damage to other components. If the throttle body is stuck closed from a small amount of deposits from fuel, it can cause overheating and extensive engine damage if left too long without being repaired. Also the vehicle itself can become extremely difficult to drive.
What repairs can fix the code?
The following are solutions that may fix this problem:
- Corrosion from connections should be removed
- Cleaning the Mass Airflow sensor or replacing it
- Coolant leak repair
- Cleaning the ABS sensor or replacing it
- Cleaning or replacing the EGR Valve
- Repairing or replacing wiring Flashing or replacing PCM
- Replace Throttle Actuator Control (rare)
A P2106 is related to and may be accompanied by the following codes:
Error Code P2104, P2105, P2110.
In conclusion, the P2106 code is a diagnostic trouble code that refers to the engine management system on the Powertrain Control Module that keeps track of the operation of the Throttle Body. The ECM is checking for unusual behavior or conditions that could cause damage to other components. If this code appears it should be taken seriously as it means there are other issues in the vehicle's systems that need to be addressed.