Circuit Description
The accelerator pedal position (APP) sensors are mounted on the accelerator pedal of the throttle actuator control (TAC) module assembly. There are 3 individual APP sensors within 1 housing. Three separate signal, low reference and 5-volt reference circuits . If only 1 APP sensor DTC is set, the redundant APP systems allow the electronic throttle control (ETC) system to continue operating normally. This DTC sets if the powertrain control module (PCM) detects a condition with more than 1 APP sensor. One APP sensor diagnostic trouble code (DTC) will not cause the Reduced Engine Power message to be displayed. Two APP sensor DTCs for the same sensor also will not cause the Reduced Engine Power message to be displayed. However, if 2 or more DTCs are set involving more than 1 APP sensor, this DTC will set and the Reduced Engine Power message is displayed.
Conditions for Running the DTC
| • | DTCs P0606, P1517, or P1518 are not set. |
| • | The ignition is ON. |
| • | The electronic throttle control (ETC) serial data is operational. |
Conditions for Setting the DTC
Two or more APP sensors are out of range, all 3 APP sensors disagree, or 1 APP sensor is out of range and the other 2 APP sensors disagree.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | If a repair is completed and the DTC was cleared using a scan tool on the same ignition cycle, the default action will not clear until an ignition cycle has occurred. |
| • | When the TAC module detects a condition within the electronic throttle control (ETC) system the PCM receives a message across serial data and more than 1 ETC system related DTC may set. This condition is due to the many redundant tests run continuously on this system. Locating and repairing 1 individual condition may correct more than 1 DTC. Be aware of this when reviewing captured DTC info. |
If the condition is intermittent, refer to Intermittent Conditions .
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
This DTC indicates that 2 or more APP sensor DTCs are also set. Refer to the APP sensor DTCs that are set and perform those diagnostic tables. Does the scan tool display any DTCs that you have not diagnosed? | -- | ||
