DTC    P0685    ECM / PCM Power Relay Control Circuit / Open

for Preparation Click here


DESCRIPTION

The battery supplies power to terminal +B and/or +B1 of the ECM even when the ignition switch is turned to off (up to 15 seconds).

P0685 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
After ignition switch is turned to off
Either of following conditions is met:
(1 trip detection logic)
  1. After ignition switch is turned to off, voltage supplied to terminal +B and/or +B1 is cut earlier than minimum threshold duration.
  2. After ignition switch is turned to off, voltage supplied to terminal +B and/or +B1 continues after threshold duration elapsed.
  1. Open in ECD relay circuit.
  2. ECD relay (integration relay)
  3. ECD MAIN fuse
  4. ECM

HINT:
If DTC P0685 is stored, the ECM does not store other DTCs.


WIRING DIAGRAM


A200296E03


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the ECM, the ECM needs Registration and Initialization (Click here).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:
When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initializations/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.

1.INSPECT INTEGRATION NO.1 RELAY

  1. Remove the integration relay from the engine room relay block.



    A200366E01

  1. Disconnect the integration relay connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1A-1 - 1B-5
    1A-1 - 1B-6
    		When battery voltage absent
    		10 kΩ or higher
    When battery voltage applied to terminals 1B-8 - 1C-6
    		Below 1 Ω

    Text in Illustration 
    *1
    		Lower side of component without harness connected
    (Integration Relay)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
Go to step 5
OK


2.CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - ECM)

  1. Disconnect the integration relay connector.



    A200293E03

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    1B-8 - A19-22 (MREL)
    		Always
    		Below 1 Ω
    1B-5 - A19-1 (+B)
    		Always
    		Below 1 Ω
    1B-6 - A19-61 (+B1)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    1B-8 or A19-22 (MREL) - Body ground
    		Always
    		10 kΩ or higher
    1B-5 or A19-1 (+B) - Body ground
    		Always
    		10 kΩ or higher
    1B-6 or A19-61 (+B1) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)
    *2
    		Front view of wire harness connector
    (to ECM)

  1. Reconnect the integration relay connector.

  1. Reconnect the ECM connector.



NG
Go to step 4
OK


3.REPLACE ECM

  1. Replace the ECM (Click here).



NEXT
Go to step 6

4.REPAIR OR REPLACE HARNESS OR CONNECTOR


NEXT
Go to step 6

5.REPLACE INTEGRATION NO.1 RELAY

  1. Replace the integration relay (Click here).


NEXT


6.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch off and wait for 30 seconds or more.

  1. Turn the ignition switch to ON.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC.

  1. Confirm that the DTC is not output again.


NEXT

END