P1120

Circuit Description
The TP sensor 1 is part of the Electronic Throttle Control System (ETC). The TP sensor us the main input to the ECM for actual throttle positioning. The ECM supplies the TP sensor 1 with a 5 volt reference and a ground circuit. The TP sensor 1 sends a voltage to the ECM on the signal circuit. The ECM then calculates the throttle angle opening based on this voltage.

Conditions for Running the DTC
The battery voltage is more than 7.0 volts.

Conditions for Setting the DTC
^ The Throttle Position (TP) sensor 1 voltage is less than 0.195 volt, or more than 4.6 volt.
^ The difference between TP sensor 1 and TP sensor 2 is more than 13 percent.
^ One of the above conditions is met for 140 ms (0.140 seconds).

Action Taken When the DTC Sets
^ The Engine Control Module (ECM) illuminates the Malfunction Indicator Lamp (MIL) on the first drive trip that the diagnostic runs and fails.
^ The ECM attempts to record the operating conditions in the Freeze Frame.
^ The vehicle will default to the limp home mode.

Conditions for Clearing the MIL/DTC
^ The ECM turns off the Malfunction Indicator Lamp (MIL) after 3 consecutive drive trips that the diagnostic runs and passes.
^ A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
^ The ECM battery voltage is interrupted.
^ The scan tool clears the MIL/DTC.

Diagnostic Aids
With the ignition ON and the engine OFF, view the TP sensor 1 and the TP sensor 2 with a scan tool. Slowly depress the accelerator pedal, the voltage on TP sensor 1 should increase steadily from 0.2 volt to about 4.6 volt. TP sensor 2 should move opposite from above 4.0 to about 0.2 volt. If one sensor value changes and the other does not, inspect the sensor circuits for high resistance or shorts. If the circuits are OK replace the TP sensor.

Notice: Refer to J 35616-A Connector Test Adapter Kit Notice in Service Precautions.

Use the J 35616-A connector test adapter kit for any test that requires probing the ECM harness connector or a component harness connector.

Check for the following conditions:
^ Poor connections at the ECM or at the component-Inspect the harness connectors for a poor terminal to wire connection.
^ Damaged harness-Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving the related connectors and the wiring harnesses. A change in the display may help locate the fault.

Refer to Symptoms for the Intermittents. Symptom Related Diagnostic Procedures

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for the proper operation of the circuit. The ECM supplies a pull up voltage of about 5 volts on the signal circuit.
4. This step tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to B+.
5. This step tests for a high resistance or an open in the ground circuit.