Mercury 525efi ECU question

ozarkdevil

New member
When you get a mercury ECU scaned is there any reason that the total recorded hours and the RPM break down hours don't match???
In other words if say the total run time hours = 100 and the RPM break down hours equal say 60 is this normal or is something going on??
 
If the ignition switch were left on without the engine running, would the ECU clock still tick away? On my boat I also hace a analog hour meter that will run without the engines on if the Ignition switch is left on.
 
Like Donskihp said, if the ECU is powered up, the total time is probably the total time the ECU is powered up.

I need to stay at a Holiday Inn Express to be sure though!
 
I suppose the key could have been left on but in that case would it not register in the 0-1999 RPM range? There is .1hrs on the 4200-4699 RPM range and nothing after that.

The boat hour meter reads 230hrs, the ECM scaned 111, 100 & 113 total hrs and the run log hours 60.4, 55.5 & 63.7
 
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I know on a 496 the "break down" hours can be cleared to zero with software, but the total hours cannot. The 525 ECU may be the same way?
 
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