2016 Sundancer 280 Mercruser 6.2L Fault Code 945-6

[T.Ski]

2016 Sundancer 280 Mercruser 6.2L. I installed the Vessel View Mobile so I could figure out why my OBD Service Soon warning is showing on my smartcraft dash guages. The Mercury Vessel View Mobile is showing Fault Code 945-6 Catalyst oxygen storage capacity port.

Is this an O2 sensor? Is there a way to test my O2 sensors to determine which one may be causeing the fault code.

 

[techmitch]

Be it your car or your boat, codes don't tell you what is wrong or what part is bad. Codes tell you what page to open up the book to start the necessary pinpoint test.
Sorry I can't be of any more help as I don't have access to those document's.

 

[Lazy Daze]

FYI, the OBD on your boat ONLY deals with the catalyst system. Nothing else. Nothing engine related.

Most commonly, the downstream O2 sensor is at fault. But it certainly could be the upstream sensor, the wiring, a clogged cat or other things. Watching the livestream using a Merc computer will help narrow it down. As Mitch pointed out, codes don't tell you what to replace. They tell you what sensor is complaining - proper diagnosis leads towards the root cause.

 

[T.Ski]

Be it your car or your boat, codes don't tell you what is wrong or what part is bad. Codes tell you what page to open up the book to start the necessary pinpoint test.
Sorry I can't be of any more help as I don't have access to those document's.

Thanks

 

[T.Ski]

FYI, the OBD on your boat ONLY deals with the catalyst system. Nothing else. Nothing engine related.

Most commonly, the downstream O2 sensor is at fault. But it certainly could be the upstream sensor, the wiring, a clogged cat or other things. Watching the livestream using a Merc computer will help narrow it down. As Mitch pointed out, codes don't tell you what to replace. They tell you what sensor is complaining - proper diagnosis leads towards the root cause.

Thanks. Do you know if I can test an O2 sensor to see if it is working?

 

[T.Ski]

Thanks. Do you know if I can test an O2 sensor to see if it is working?

Thanks

Do you know if i replace the o2 sensor, do i still need someone to clear the code, or will it clear on it's own?

 

[techmitch]

FYI, the OBD on your boat ONLY deals with the catalyst system. Nothing else. Nothing engine related.

Most commonly, the downstream O2 sensor is at fault. But it certainly could be the upstream sensor, the wiring, a clogged cat or other things. Watching the livestream using a Merc computer will help narrow it down. As Mitch pointed out, codes don't tell you what to replace. They tell you what sensor is complaining - proper diagnosis leads towards the root cause.

Yep, live data is your friend/first step here. Then testing all circuits between the offending sensor and the ECU for short's to power or ground with both disconnected. Next would be to test the integrity of all circuits with both a voltage drop test and also load testing.

 

[Espos4]

Or just swap sensors from side to side. Reset the codes and drive it until an error code populates.

 

[GirlyGirl1999]

+1 to both Mitch and LazyDaze. I found this:
http://download.brunswick-marine.co...ercruiser/gasoline/8m0086113/8m0086113_2b.pdf
It is pretty technical but if you scroll to page 10 I think it speaks to “storage capacity” I’m not a Mercury guru by any sense but I do own Jaguars, which is why I have a pretty smart scanner and know that live data is what you want. The document speaks to 2 stage or 3 stage cats, so no sure what you have. On my cars I am a big proponent of shift a part (02 sensor) and see if the problem shows up on the port side.
Not sure of your confidence level on working on the motor but sometimes at least going in to the mechanic with information helps.
My .02
Jon

 

[GirlyGirl1999]

Or just swap sensors from side to side. Reset the codes and drive it until an error code populates.

I was typing while you answered. +1