DTC P0685:00 [SKYACTIV-G 2.0]

id0102h1302800

DTC P0685:00

Main relay control circuit open
DETECTION CONDITION
•  This DTC sets when the ignition switch position run circuit indicates the key is in the off, ACC, or LOCK position, and the amount of time the PCM remains powered through the PCM power relay exceeds a predetermined amount of time.
Diagnostic support note
•  This is a continuous monitor (CCM).
•  The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
•  PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle.
•  FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
•  The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
—
POSSIBLE CAUSE
•  Poor contact of battery terminal
•  Main relay malfunction
•  Short to ground or open circuit in main relay power supply circuit:
―  Short to ground in wiring harness between ENG MAIN 40 A fuse and main relay terminal D
―  ENG MAIN 40 A fuse malfunction
―  Open circuit in wiring harness between battery positive terminal and main relay terminal D
•  ENG INJ 15 A fuse malfunction
•  Short to ground in wiring harness between the following terminals:
―  Main relay terminal C—PCM terminal 2S
―  Main relay terminal C—PCM terminal 2T
•  PCM connector or terminals malfunction
•  Open circuit in wiring harness between PCM terminal 1BZ and body ground
•  Open circuit in wiring harness between PCM terminal 2AA and body ground
•  Open circuit in wiring harness between the following terminals:
―  Main relay terminal C—PCM terminal 2S
―  Main relay terminal C—PCM terminal 2T
•  PCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA (Mode 2)/snapshot data been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (Mode 2)/snapshot data on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT FOR POOR CONTACT OF BATTERY TERMINAL
•  Inspect battery terminals for poor contact.
•  Are the battery terminals connected correctly?
Yes
Go to the next step.
No
Connect the battery terminals correctly, then go to Step 11.
4
INSPECT MAIN RELAY
•  Switch the ignition to off.
•  Remove the main relay.
•  Inspect the main relay.
•  Is there any malfunction?
Yes
Replace the main relay, then go to Step 11.
No
Go to the next step.
5
INSPECT MAIN RELAY POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
•  Main relay is removed.
•  Measure the voltage at the main relay terminal D (wiring harness-side).
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the ENG MAIN 40 A fuse.
•  If the fuse is blown:
―  Repair or replace the wiring harness for a possible short to ground.
―  Replace the fuse.
•  If the fuse is deteriorated:
―  Replace the fuse.
•  If the fuse is normal:
―  Repair or replace the wiring harness for a possible open circuit.
Go to Step 11.
6
INSPECT ENG INJ 15 A FUSE
•  Remove the ENG INJ 15 A fuse.
•  Inspect the ENG INJ 15 A fuse.
•  Is there any malfunction?
Yes
If the fuse is blown:
•  Repair or replace the wiring harness for a possible short to ground.
•  Replace the fuse.
If the fuse is deteriorated:
•  Replace the fuse.
Go to Step 11.
No
Reinstall the ENG INJ 15 A fuse, then go to the next step.
7
INSPECT PCM POWER SUPPLY CIRCUIT FOR SHORT TO GROUND
•  Main relay is removed.
•  Inspect for continuity between main relay terminal C (wiring harness-side) and body ground.
•  Is there continuity?
Yes
If the short to ground circuit could be detected:
•  Repair or replace the wiring harness for a possible short to ground.
If the short to ground circuit could not be detected:
•  Replace the PCM (short to ground in the PCM internal circuit).
Go to Step 11.
No
Go to the next step.
8
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 11.
No
Go to the next step.
9
INSPECT PCM GROUND CIRCUIT FOR OPEN CIRCUIT
•  Main relay is removed.
•  Verify that the PCM connector is disconnected.
•  Inspect for continuity between the following harnesses:
―  PCM terminal 1BZ (wiring harness-side)—Body ground
―  PCM terminal 2AA (wiring harness-side)—Body ground
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to Step 11.
10
INSPECT PCM POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
•  Main relay is removed.
•  Verify that the PCM connector is disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  Main relay terminal C—PCM terminal 2S
―  Main relay terminal C—PCM terminal 2T
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
11
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Start the engine and warm it up completely.
•  Perform the Pending Trouble Code Access Procedure.
•  Is the PENDING CODE for this DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.0].)
No
DTC troubleshooting completed.