P0685 - Electronic Control Module (ECM)/Powertrain Control Module (Pcm) Power Relay Control Circuit/Open

2009 Mercury Milan Premier, 3.0 1, AWDSECTION P0685 - Electronic Control Module (ECM)/Powertrain Control Module (Pcm) Power Relay Control Circuit/Open
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
P0685 - ELECTRONIC CONTROL MODULE (ECM)/POWERTRAIN CONTROL MODULE (PCM) POWER RELAY CONTROL CIRCUIT/OPEN

Description:  This DTC sets when the ignition switch position run (ISP-R) 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.
Possible Causes: 
  • PCM relay control (PCMRC) circuit short to ground in the harness
  • Damaged PCM power relay
Diagnostic Aids:  Ability to communicate with the PCM when the key is in the OFF, ACC, or LOCK position indicates a hard fault.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All   refer to PINPOINT TEST B .
RENDER: 1.0x

NO RELATED

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