1. DTC P0685 description
The ECM main relay is energized in order to supply battery power to the ECM through the relay switch side when the ECM receives an ignition switch ON signal. When the ignition switch turns OFF, voltage application to the ECM main relay stops after a predetermined length of time has passed. If the ECM detects a low voltage condition in the ECM main relay voltage supply circuit when the ECM main relay is commanded ON, the DTC is set.
2. Condition for setting DTC P0685
Condition for running the DTC
- The battery voltage is 9 to 16 V.
- 3 seconds or more have passed since the ignition switch was turned ON.
- DTC P060B is not set.
Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC P060B Internal Control Module A/D Processing Performance".
Condition for setting the DTC
- The ECM detects a low voltage condition in the ECM main relay voltage supply circuit for 3 seconds when the relay is commanded ON.
3. Action taken when DTC P0685 sets
- The ECM illuminates the SVS indicator light. Refer to Action taken when DTC sets - Type C.
Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".
4. Condition for clearing DTC P0685
- Refer to Condition for clearing the SVS indicator light/DTC - Type C.
Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".