P1682

DTC P1682

Circuit Description

The Throttle Actuator Control (TAC) System determines the drivers intent and then calculates the appropriate throttle response. The TAC system achieves throttle positioning by providing a pulse width modulated voltage to the TAC motor. The powertrain control module (PCM) is the control center for the TAC system. Ignition 1 voltage is supplied on 2 separate circuits to the PCM. If the PCM detects a voltage difference between the 2 circuits, DTC P1682 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1682 Ignition 1 Switch Circuit 2

Conditions for Running the DTC

* The ignition is in Unlock, Accessory, Run, or Crank mode.
* DTC P1682 runs continuously when the above condition is met.

Conditions for Setting the DTC

The ignition 1 voltage is less than 10 volts for more than 10 seconds.

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.
* Clear the DTC with a scan tool.

Test Description

Step 1 - Step 10:

The numbers below refer to the step numbers on the diagnostic table.
3. This step determines if there is voltage present to the ECM fuse.
5. This step determines if voltage is present at the PCM.
6. This step determines if the PCM ignition 1 voltage circuit is shorted to ground.