P1285

CIRCUIT DESCRIPTION
The Accelerator Pedal Position (APP) sensors are located within the Throttle Actuator Control (TAC) module assembly. The TAC module assembly is mounted to the accelerator pedal bracket. There are 3 individual APP sensors within the TAC module. Three separate signal circuits, low reference circuits, and 5-volt reference circuits are used in order to determine the accelerator pedal position. The APP sensor signal voltages increase when the accelerator pedal is depressed.

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0606, P1517, or P1518 are not set.
^ The ignition switch is in the crank or the run position.

CONDITIONS FOR SETTING THE DTC
The APP sensor 3 voltage is less than 0.68 volts, or more than 4.5 volts.

ACTION TAKEN WHEN THE DTC SETS
^ The control module stores the DTC information into memory when the diagnostic runs and fails.
^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
^ The driver information center, if equipped, may display a message.

CONDITIONS FOR CLEARING THE DTC
^ 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 non-emission related diagnostic.
^ Use a scan tool in order to clear the DTC.

DIAGNOSTIC AIDS

IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Verify that the gaskets are installed correctly. The gaskets prevent intrusion of contaminates.

When the TAC module detects a condition within the Electronic Throttle Control (ETC) system the Powertrain Control Module (PCM) receives a message across serial data and more than 1 ETC system related DTC may set. This 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 DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.

TEST DESCRIPTION

Steps 1-7:

The number below refers to the step number on the diagnostic table.
7. When the TAC module detects a condition within the ETC system the PCM receives a message across serial data and more than 1 ETC system related DTC may set. This 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.