Merc overheat codes
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![Angry](/forums/images/icons/icon8.gif)
My port 496 Mag is going into Guardian Mode at 4000+ RPM. I have a Merc scan tool that reads the codes, which is showing "overheat", but the temp guage is never going above 170 degrees. I can run all day under 4000 RPM with no issues. Does anyone know if the Merc Scan tool gives the same code reading for low water pressure as overheat?
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The fault should be specific to either an exhaust manifold overtemp (EMCT Overheat) or Engine Coolant overheat (ECT Overheat), or Seapump pressure (Sea Pmp Pressure Low). Each one should set a different Fault code.
You could check system temps with a infrared to confirm the fault(s).
Dave
You could check system temps with a infrared to confirm the fault(s).
Dave
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