Description
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. If the PCM determines that current flow of the TAC motor is too high, a DTC P2103 sets. For additional information on the operation of the TAC system, refer to Throttle Actuator Control (TAC) System Description .
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P2103 Throttle Actuator Control Motor Circuit High Voltage
Conditions for Running the DTC
| • | The power supply to the TAC motor is at least 8 volts. |
| • | DTC P2103 runs continuously once the above condition has been met. |
Conditions for Setting the DTC
The TAC motor current is more than 7 amps for 600 milliseconds.
OR
The TAC motor current is more than 10 amps for 100 milliseconds.
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL). |
| • | The PCM stores the conditions that were present when the DTC set as Freeze Frame data. |
| • | The engine will operate in the reduced power mode and the TP sensor angle will default to 19 percent. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL on the third consecutive trip in which the diagnostic runs without a fault. |
| • | The PCM clears a History DTC after 40 consecutive warm-up cycles without a fault. |
| • | You use the scan tool Clear DTC Information function. |
Diagnostic Aids
| • | TAC Motor Current is displayed on the scan tool, but the displayed value freezes when the MIL illuminates and the DTC sets. |
| • | The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 11-15 percent. This is referred to as the rest position. |
| • | The throttle valve should move open and to the closed position without binding under the normal spring pressure. |
| • | The throttle should NOT be free to move open or closed WITHOUT spring pressure. |
| • | For an intermittent condition, refer to Intermittent Conditions . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
DTC P2118 can set because of an open or a short to ground in the TAC ignition voltage circuit. When this fault occurs, a sudden surge of current can be detected in the TAC motor control circuits, causing a DTC P2103 to also set. Therefore, DTC P2118 must be fixed first.
-
This step determines if the condition that set the DTC still exists.
-
When the TAC module is disconnected the motor control circuits should have no voltage. If voltage is measured on either circuit, there is a short to voltage or a faulty PCM.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
Is a DTC P2118 also set? | -- | Go to DTC P2118 | Go to Step 3 | |
Did DTC P2103 set? | -- | Go to Step 5 | Go to Step 4 | |
4 |
Did DTC P2103 set? | -- | Go to Step 5 | Go to Diagnostic Aids |
Was the voltage measured on both circuits less than the specified value? | 1 V | Go to Step 8 | Go to Step 6 | |
6 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 |
7 | Replace the powertrain control module (PCM) . Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- |
8 | Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 10 |
10 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
