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P0123

Diagnostic Chart (Part 1 Of 2):




Diagnostic Chart (Part 2 Of 2):




Schematic:




CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) supplies a 5.0 volt reference signal and a ground to the sensor. The TP sensor sends a voltage signal back to the PCM relative to the throttle plate opening. The voltage will vary from approximately 0.35 volt at closed throttle, to more than 4.65 volts at Wide Open Throttle (WOT).

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0107 or P0108 are not set.
^ The engine is running.
^ The MAP is less than 60 kPa.
^ The engine speed is less than 1500 RPM.
Or
^ DTCs P0107 or P0108 are not set.
^ The engine is running.
^ The MAP is more than 60 kpa.
^ The engine speed is more than 1500 RPM.

CONDITIONS FOR SETTING THE DTC
^ The TP sensor voltage is more than 3.9 volts for 13.75 seconds when the engine speed is less than 1500 RPM.
^ The TP sensor voltage is more than 4.8 volts when the engine speed is more than 1500 RPM.

ACTION TAKEN WHEN THE DTC SETS
^ The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.
^ The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame and Failure Records buffers.
^ A history DTC stores.
^ The coolant fan turns ON.
^ The TP angle will default to 0 percent when the vehicle speed is less than 3 km/h (2 mph) and 10 percent when the vehicle speed is more than 3 km/h (2 mph) (The scan tool will display the defaulted value).

CONDITIONS FOR CLEARING THE MIL/DTC
^ The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
^ A history DTC will clear after 40 consecutive warm-up cycles without a fault.
^ Use a scan tool to clear the DTCs

DIAGNOSTIC AIDS
If DTC P0123 cannot be duplicated, the information included in the Freeze Frame data can be useful. Use the scan tool DTC information data to determine the status of the DTC.

With the ignition ON and the throttle at closed position, the voltage should read between 0.20-0.90 V. Voltage should increase steadily to more than 4.5 V at wide open throttle.

TEST DESCRIPTION
The numbers below refer to the step numbers in the diagnostic table.
2. If the throttle position (TP) signal measures more than 4.8 volts, then the condition exists.
3. With the TP sensor disconnected, and if the PCM and the wiring are okay, the TP signal should be less than 0.25 volt. This test could set a DTC P0122.