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

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DTC P0689: ELECTRONIC CONTROL MODULE (ECM)/POWERTRAIN CONTROL MODULE (PCM) POWER RELAY SENSE CIRCUIT LOW

Description:	The powertrain control module (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 .