P1682
DTC P1682
CIRCUIT DESCRIPTION
The ignition 1 voltage circuit supplied by the powertrain relay is used to power the throttle actuator control (TAC) circuitry internal to the engine control module (ECM). The second ignition 1 voltage circuit is supplied by the ignition switch through the ECM 2 fuse, and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition 1 voltage circuits, DTC P1682 will set.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P1682 Ignition 1 Switch Circuit 2
CONDITIONS FOR RUNNING THE DTC
- The ignition is ON.
- The powertrain relay is commanded ON.
- DTC P1682 runs continuously.
CONDITIONS FOR SETTING THE DTC
The ECM detects that the voltage level difference is greater than 3 volts between the ignition switch, ignition 1 voltage circuit and the ETC ignition 1 voltage circuits for more than 3 seconds.
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 the information in the Freeze Frame/Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the 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.
TEST
