Mercury 525efi ECU question

[ozarkdevil]

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??

[Donskihp]

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.

[MacGyver]

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!

[ozarkdevil]

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

[MOBILEMERCMAN]

The break in time is part of the total run time.

Plus it is run time not key on time.

[hessdk]

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?