Mercruiser 496 MAG Diagnostic Port

[SimonB]

Hi there

Looking for some help on location of the dianostic port for my 496MAG (2004 496 MAG with PCM 555 / Bravo III combo in a Rinker Captive 282). I have the Diacom software but could not find the connector. Please help!

Thanks

 

[newport dave]

Re: Mercruiser 496 MAG Diagnostic Port

You should find a black four pin connector on the port side of the throttle body. It may have a dust cap on it and it could have a depthsounder connected to it. Shouldn't be too hard to find. Once connected, click on the "Codes" tab at the top of the screen, then click on the "Faults" button to show the list of active faults. Next click on the "H" button to retrieve the contents of the Freezframe memory. If you need help understanding the data, post it and I (or someone else) wiil help.

 

[SimonB]

Re: Mercruiser 496 MAG Diagnostic Port

Great! Thanks for the help. It is labelled TACH. Threw me off!

 

[Don S]

Re: Mercruiser 496 MAG Diagnostic Port

What color wires are going to it? I don't think the tach lead is what you want.

 

[SimonB]

Re: Mercruiser 496 MAG Diagnostic Port

Thanks for your help. I ran the software and got these codes.
Power steering fluid was low, so I topped off. Motor starts but does not idle. Is there a place I can research these other codes?


Current ECM Codes

Sensor Fault, click Read Fault button for details

Trouble Code List:
PITOT CKT LO Code is active
FUEL LVL CKT HI Code is active
STEER CKT HI Code is active
TRIM CKT LO Code is active
FUEL LVL2 CKT H Code is active

 

[newport dave]

Re: Mercruiser 496 MAG Diagnostic Port

None of those codes mean anything important. They all relate to optional sensors that are not connected on your engine. What about the contents of the Freezframe memory? It may or may not help, but it's worth checking.

 

[wifd401]

Re: Mercruiser 496 MAG Diagnostic Port

Hi
i have a similar problem with a pair of these engines in a 2004 fountain. i have the same codes except i also have a raw water hi pressure code and in the live data it is 46 psi> the other engine the data shows 2.6 psi and no alarms. can anyone help ??? thanks for any help.

 

[Don S]

Re: Mercruiser 496 MAG Diagnostic Port

Welcome to iboats wifd,

You really need to start a new thread with your problem. Not just stick your question at the end of someone elses 2 year old post where it will not be seen by many.