Idle Learn Procedure

TP SENSOR/IDLE LEARN PROCEDURE
A Throttle Position (TP) sensor learn routine has been implemented in the PCM software to allow the PCM to correct or offset the closed throttle signal value of the TP sensor. This is necessary because of manufacturing tolerances during minimum air adjustment. The TP sensor is not adjustable on the throttle body. If an improper TP learned value is maintained by the PCM, a closed throttle engine sail-on or stall condition may occur. Performing the TP SENSOR LEARN procedure lets the PCM learn the correct TP sensor offset.

An IDLE LEARN routine has been implemented in the PCM software to allow for a loss of air flow through the throttle body during closed throttle operation. This reduction in air flow can be caused by deposit buildup on the throttle valve.

The IDLE LEARN routine is different from the TP SENSOR LEARN routine of the PCM. TP SENSOR LEARN is performed by the PCM after the ignition is turned to "OFF." IDLE LEARN is performed by the PCM when the engine is running and specific conditions are met.

The IDLE LEARN routine of the PCM calculates a throttle angle correction or offset that is used during closed throttle idle control. If an improper throttle angle offset is maintained by the PCM, a closed throttle engine sail-on or stall condition may occur. Performing the IDLE LEARN procedure lets the PCM learn the correct throttle angle offset.

Make Sure nothing is touching or obstructing the accelerator or brake pedals during the TP SENSOR/IDLE LEARN procedure because this will prevent the PCM from performing the learn routine.

The TP SENSOR/IDLE LEARN procedure should be performed when:

- The TP sensor is replaced.
- The ISC motor is adjusted or replaced.
- The throttle body is replaced.
- The PCM is replaced.
- The EEPROM is replaced.

To perform TP SENSOR/IDLE LEARN:

1. Outside air temperature is at least 10°C (50°F) so that the A/C compressor will turn on.
2. Start the engine.
3. Allow the vehicle to idle continuously until the coolant temperature is 80°C, then idle an additional 5 minutes.
4. Using the Tech 1 enter misc test ISC. Then using ISC/IDLE LEARN, follow the step by step procedure outlined on the display.

NOTE: Because of the engine load differences with the A/C "ON" versus "OFF," TP SENSOR/IDLE LEARN must be allowed during both conditions.