The throttle valve in the throttle body utilizes a throttle return spring to assist in positioning the throttle valve at a resting or default position. The powertrain control module (PCM) uses driver input from the accelerator pedal position (APP) sensor in order to calculate the desired throttle position. The PCM sends the desired throttle position or target value to the throttle actuator control (TAC) module. The TAC module achieves the desired throttle position by commanding the throttle control motor to position the throttle valve at the target value. The TAC module then compares the throttle position (TP) sensor 1 value to the target value. If necessary, the throttle control motor is moved slightly in order to obtain the exact target value position.

P2102

When the duty cycle of the open command for the TAC motor is greater than 80 percent, the TAC motor current is less than 0.5 amp.

P2103

DTC P2102 and P2103 are Type A DTCs.

The PCM enters the Fail-Safe function operating in the reduced power mode and the TP sensor angle will default to 19 percent.

DTC P2102 and P2103 are Type A DTCs.

Schematic Reference

Engine Controls Schematics

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, observe the DTC information with a scan tool. Verify DTC P2118 is not set.

⇒	If DTC P2118 is set, diagnose the DTC first. Refer to DTC P2118.

2. Ignition ON, rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times. DTCs P2102 or P2103 should not set.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Important: 

•	The TAC system DTCs must be cleared before testing for voltage. The PCM will not provide voltage to the TAC motor circuits when a TAC or TP sensor DTC is set.

•	The engine cannot be running when testing for voltage. If the engine is started, the TAC system DTC will set and the PCM will not provide voltage to the TAC motor circuits.

•	Do not disconnect the TAC module harness connector. A TP sensor DTC will set when the ignition is turned ON.

•	Do not disconnect the PCM harness connector. Test for voltage at the backside of the PCM harness connector.

1. Ignition ON, test for B+ between ground and the TAC motor control low and TAC motor control high circuit terminals as listed below:

•	TAC motor control low circuit terminal X2-3

•	TAC motor control high circuit terminal X2-4

⇒

If less than the specified range, test the appropriate TAC motor control circuit for a short to ground or an open/high resistance. If the circuit tests normal, disconnect the TAC module harness connector and test for greater than 4 ohms between terminal 1 and terminal 2 of the TAC module. If less than the specified range, replace the throttle body assembly.

2. Ignition OFF, disconnect the harness connector at the TAC module.

Important: With the TAC module disconnected, a TP sensor DTC will set and the PCM will not provide voltage to the TAC motor circuits.

3. Ignition ON, test for 0 volts between ground and the TAC motor control low circuit terminal 1 and the TAC motor control high circuit terminal 2.

⇒	If greater than the specified range, test the appropriate TAC motor control circuit for a short voltage. If the circuit tests normal, replace the PCM.

4. If all circuits test normal, test or replace the throttle body assembly.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.