Throttle Actuator Control System - Forced Limited Power
P2106 indicates that the Powertrain Control Module (PCM) has detected a fault in the throttle actuator control system and has entered a fail-safe mode, limiting engine power to prevent damage. This code is triggered when the PCM commands the throttle to a specific position but the actual position does not match, or when there is an electrical fault in the throttle actuator circuit. The system reduces power to allow the vehicle to be driven to a repair facility.
1. Most Common Causes
- Faulty throttle body (TAC motor or internal TPS sensor)
- Faulty accelerator pedal position (APP) sensor
- Open, short, or high resistance in TAC/APP wiring or connectors
- Excessive carbon/soot buildup on throttle plate causing mechanical binding
- Internal PCM failure
- Low battery voltage or fault in throttle control module power circuit
2. Symptoms You Will Notice
- Reduced engine power (limp mode)
- Check Engine Light illuminated
- Poor acceleration or hesitation
- Engine may not exceed certain RPM
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data.
Step 2: Inspect throttle actuator wiring and connectors for damage, corrosion, or loose connections.
Step 3: Test throttle actuator motor resistance and operation using a multimeter or scan tool.
Step 4: Check accelerator pedal position sensor signal and calibration.
Step 5: If all else is normal, update PCM software or replace PCM.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
The vehicle will enter limp mode with reduced power, which may be unsafe for highway driving. It is best to drive cautiously to a repair shop.
How much does it cost to fix?▼
Repair costs vary from $150 to $400 depending on the cause, with throttle actuator replacement being the most common fix.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.