P2106, p2110

[06T200]

May need to do a throttle body relearn. Is done every 15 ignition cycles...

The engine control module (ECM) stores values that include the lowest possible throttle position (TP) sensor positions and the rest positions. These values will only be erased or overwritten if the ECM is reprogrammed or if a throttle body relearn procedure is performed. Observe, if the battery is disconnected, the ECM will immediately perform a throttle body relearn procedure when the ignition is turned ON.

The ECM performs a relearn procedure twice and compares the results. If the results are nearly the same, the values are stored and the learn procedure is complete. The following is when the ECM performs a learn procedure:

The ignition is ON.



The engine is cranking.



Deceleration



The ignition is cycled OFF.


The ECM performs the learn procedure every 15 ignition cycles.

The ECM commands the throttle plate from the rest position to full closed, then stores TP sensor 1 and 2 voltages. This procedure takes less than 1 second. If any faults occur in the throttle actuator control (TAC) system, a DTC sets.


More:

There are 4 reduce power modes that the engine control module (ECM) can default to if an error is detected in the throttle actuator control (TAC) system. The ECM monitors for the following conditions:

Accelerator pedal position (APP) sensor 1 or 2 circuit fault



APP sensor correlation fault



A 5-volt reference circuit fault



Battery voltage is less than 8 volts or greater than 24 volts.


If the ECM detects any of the above conditions, the ECM enters a Limited Performance reduced power mode. In the Limited Performance mode, the engine torque is limited. The ECM remains in this reduced power mode during the entire ignition cycle even if the fault is corrected.

If there is no APP sensor information, the system enters a Forced Idle reduced power mode. In the Forced Idle mode, the ECM uses a default APP sensor position that is calculated from the brake switch, transmission gear position, and vehicle speed. The vehicle can be driven up to 32 km/h (20 mph) in this mode be engaging the transmission into gear and releasing the brake pedal.

If there is a condition with the TAC circuits, throttle actuator command vs actual position fault, or a TP sensor 1 or 2 circuit fault, the ECM enters a Power Manage reduced engine power mode. In the Power Manage mode, the throttle plate is not controlled. The engine torque is controlled to the desired value using cylinder shutoff and spark retard. The engine will idle or cruise with 2 cylinders enabled and accelerate with all 4 cylinders.

If the ECM detects a severe failure in the TAC system, the ECM enters a Forced Shutdown mode. In this mode, the ECM disables the TAC system, the fuel system, and the ignition system so the engine will not start. The Forced Shutdown mode occurs when the ECM detects a severe internal ECM condition, the throttle plate is stuck open, or a large intake manifold vacuum leak is detected.