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TP Sensor/Idle Learn Procedure

A 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, TP sensor manufacture and because the TP sensor is not adjustable on the throttle body. If an improper TP sensor offset 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.

CAUTION: 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.
WARNING: High electrical loads may disable TP SENSOR/IDLE LEARN. Components that may produce a high electrical load are the headlamps, the rear defogger, high HVAC blower and cooling fans. If difficulty is encountered learning TP SENSOR/IDLE LEARN values (i.e. Code P080 remains current), turn "OFF" these high electrical loads. Also, it is important to accelerate the engine above 1000 RPM after turning "OFF" the above components because the PCM will think it is still under a high electrical load until it checks the system again (when engine RPM exceeds 1000 RPM). Furthermore, since the cooling fans can not be manually controlled, engine coolant temperature must be below 105°C and A/C refrigerant temperature must be below 51°C.

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

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. After 5 minutes, enter diagnostics (engine still running).
  5. Turn ignition to "OFF".
  6. Wait a minimum of 20 seconds.
  7. Turn ignition to "ON" (engine not running).
  8. Enter diagnostics.
  9. Turn ignition to "OFF".
  10. Wait a minimum of 20 seconds.
  11. Turn ignition to "ON" (engine not running).
  12. Enter diagnostics.
  13. Turn ignition to "OFF".
  14. Wait a minimum of 20 seconds.
  15. Start the engine.
  16. Apply the brakes and place the transaxle in "DRIVE" range.
  17. Turn the Electronic Climate Control (ECC) to "OFF" and allow the engine to idle for 30 seconds.
  18. Turn the ECC to "AUTO", verify A/C compressor engagement occurs. Allow the engine to idle for another 30 seconds.
  19. Place the transaxle in "PARK" range and turn ignition to "OFF".
CAUTION: Because of the engine load differences with the A/C "ON" versus "OFF", TP SENSOR/IDLE LEARN must be allowed during both conditions.
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