DTC P0689: Electronic Control Module (ECM)/Powertrain Control Module (Pcm) Power Relay Sense Circuit Low

2005 Ford GTSECTION DTC P0689: Electronic Control Module (ECM)/Powertrain Control Module (Pcm) Power Relay Sense Circuit Low
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P0689 - ELECTRONIC CONTROL MODULE (ECM)/POWERTRAIN CONTROL MODULE (PCM) POWER RELAY SENSE CIRCUIT LOW

Description:  The PCM monitors the voltage on the ignition switch position run (ISP-R) and the fuel injector power monitor (INJPWRM) circuits. This DTC sets when the voltage on the ISP-R and the INJPWRM circuit voltages do not correspond for a calibrated period of time.
Possible Causes: 
  • Ignition circuit fuse
  • ISP-R circuit open in the harness
  • ISP-R circuit short to ground in the harness
  • Fuel injector voltage power (VPWR) circuit short to voltage
  • Fuel injector power monitor (INJPWR) circuit short to voltage
  • Damaged ignition switch
  • Damaged fuel pump relay
  • Damaged PCM power relay
Diagnostic Aids:  The INJPWRM PID voltage reading should be 0 volts when the ignition is in the OFF, ACC or LOCK position.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST B .
RENDER: 1.0x

NO RELATED

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