P0122

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 over 4.65 volts at Wide Open Throttle (WOT).

CONDITIONS FOR RUNNING THE DTC
The engine is running.

CONDITIONS FOR SETTING THE DTC
The TP sensor reads less than 0.10 volt for 6.25 seconds.

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
The scan tool reads the Throttle Position (TP) in volts. The TP should read approximately 0.3-0.85 volts with the throttle closed and the ignition ON or at idle. The voltage should increase at a steady rate as the throttle is moved toward wide open throttle (WOT). The scan tool will also read the throttle angle percentage, from 0 percent at closed throttle to 100 percent at wide open throttle.

Refer to A Diagnostic Starting point

Scan the TP sensor signal while depressing the accelerator pedal with the ignition turned ON, leaving the engine OFF. The display should vary from less than 1.25 volts (1250 mV) when the throttle was closed to more than 4.5 volts (4500 mV) when the throttle is held at the wide open throttle (WOT) position. An intermittent may be caused by any of the following conditions:
^ A faulty connection
^ Rubbed-through wire insulation
^ A broken wire inside the insulation

Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in Diagrams. If a repair is necessary, then refer to Wiring Repairs or Connector Repairs in Diagrams.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. If the TP signal measures less than 0.25 volt, then the low voltage condition exists.
5. If the PCM recognizes the high signal voltage, the PCM and the wiring are okay.
8. The 5-volt reference of the PCM supply is shared by the FTP, the TP, and the A/C position sensors. A short to ground at ANY of these sensors 5-volt reference circuits OR an internally shorted sensor may cause this DTC to set. In order to determine the location of a shorted 5-volt reference supply, disconnect the sensors one at a time, beginning with the A/C sensor.
12. The sensor connectors must remain disconnected while the PCM connector remains connected for this step. The PCM terminals are spliced together inside the PCM. When inspecting the 5-volt reference circuit for a short to ground, all the 5- volt reference circuits must also be inspected.