Code result
P0689
ECM or PCM Power Relay Sense Circuit Low
Moderate severity
What it means
The voltage sense line that confirms the main ECU power relay has actually closed reads low - either the relay is not closing or the sense line is shorted to ground.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Relay does not close
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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