The PCM checks the main relay control circuit every 10 seconds. If the PCM detects an open or short in the control circuit it will set a DTC P0685.
Item | Detecting Condition | Possible cause |
DTC Strategy |
•
Detects a short to ground, short to battery (+), or open control circuit on the main relay | 1. Poor Connection 2. Open or short in control circuit 3. Faulty Main Relay 4. Faulty PCM |
Enable Conditions |
•
Engine Running
•
Ignition Voltage between 11V and 16V | |
Threshold value |
•
Open or Short in circuit | |
Diagnosis Time |
•
Continuous (More than 5 sec. failure for every 10 sec. tes) | |
MIL On Condition |
•
DTC only (NO MIL ON) |
※ If Main relay has a fault (ex. when the engine is running), the DTC’s, P0638/P0685/P1295/P2106, can set at the same time.
<DTC Name>
- P0638 Throttle Actuator Control Range/Performance(Bank 1)
- P0685 PCM/PCM Power Relay Control Circuit /Open
- P1295 Throttle Actuator Control System - Power Management
- P2106 Throttle Actuator Control System - Forced Limited Power
