496 Mag Ho Help
 

Need Some Help Here, I Don't Have The Service Manual On This Unit But Here's What I Need.
The Unit Is Telling Me It Has A Bad Sensor
Fault Active
Pitot Ckt Low Yes
Fuel Lvl Ckt Hi Yes Arrow Down
Steer Ckt Hi Yes
Fuel Lvl2 Ckt H Yes Arrow Up

I Know The "pitot" Is Because The Boat Is Not Moving

The "steer " Where Is The Outdrive Steering Position Sensor

And Is The Fuel Related To The Level In The Tank?

Re: 496 Mag Ho Help
 

THATS WHERE I GOT THE ONES I LISTED

Re: 496 Mag Ho Help
 

We Put A Sea Water Pump On It And It Ran Fine For 30-45 Min Then It Was Going In And Out Of Guardian Mode. Water Temp, Oil Was Fine. Idle Was Good But When It Would Get Up On Plane It Would Run About 45 Sec. And The Alarm Would Go Off And If I Didn't Pull The Sticks Back It Would Kill, If I Bid Pull Back To Idle It Would Stay Running.
I Know The Water Pump Has A Water Pressure Switch On The Outlet Side Of The Pump. At The Time I Thought It May Be Loosing Water Pressure And Causing The Alarm, But Thats Not What The Ddt Says.

Re: 496 Mag Ho Help
 

The Technician Reference Manual FOR THE DDT Reffers To The (fuel Lvl Ckt Hi) As The Same As (fuel Lvl In Hi) Or Fuel Level sensor Input Is High.
I Don't Know Where The High Fuel Level Could Be.
The Fuel Tank Only Has A Level Sender To A Gauge And It Don't Have A Vapor Tank.

Re: 496 Mag Ho Help
 

Racer,
The codes you listed are generally systems that are available, but rarely used. These will always show up using the scan tool as active faults, being they are not connected. However none of these should be setting off the guardian mode. What you may have is a fault that is listed in the fault history that is giving you the problem. A series of faults will not show active when the throttles are retarded, the system resets itself, but it should be stored in fault history.

Re: 496 Mag Ho Help
 

I CHECKED THE HISTORY AND OTHER THAN THESE THE ONLY OTHE CODE WAS FOR PORT OVER TEMP AND IT WAS 90 SEC. BUT IT HAPPEN EARLY .
THE GUARDIAN HAD 556 SEC TOTAL. WHAT SHOULD THE WATER PSI BE AT IDLE AND WOT

Re: 496 Mag Ho Help
 

I CHECKED IDLE AT 1.4, THATS GOOD. GUESS I'LL TAKE TO THE WATER .

Re: 496 Mag Ho Help
 

I ran into a similar situation. It was a faulty oil pressure senderfor the ECU. As speed came up the oil pressure would drop until it shut down. There was no fault indicator set and you could only see it in real time. The oil pressure gauge showed good oil pressure the whole time. I would suggest running the boat with the scan tool connected. When it goes into limp mode, look at all the readings and see which one is wrong.

Re: 496 Mag Ho Help
 

GOOD IDEA, KEEP THEM COMING.

Re: 496 Mag Ho Help
 

I am not sure what the exact water psi is, but if it was a water pressure issue, you should have had a Sea water press fault locked in. If I am not mistaken, I believe the port overtemp may be referring to the port exhaust temp over heating. This will set off the guardian. If this is an actual temp problem, the exhaust would have become very hot. It may be a water flow issue through the port exhaust.

Re: 496 Mag Ho Help
 

IF THE CODE WAS SET ON THE PORT EXH TEMP FOR 90 SEC.
I WOULD THINK THAT THE GUARDIAN TIME WOULD MATCH OR BE CLOSE TO THE SAME NOT 556 SEC.

Re: 496 Mag Ho Help
 

As bobl mentioned, having a scan tool hooked up while testing should show the active fault causing the alarm/Gaurdian mode.

Or clear the fault history and freezframe memory and retest. It should be easy to tell what the problem is/was when reviewing the new history.

Sea Pump Presssure can be eliminated as a possible cause by disconnecting it. It will default to 46PSI.

Exhaust manifold overheat should be easily confirmed by checking with infrared thermometer. Temp over 212 degrees will trigger alarm/Gaurdian mode.

Dave

Re: 496 Mag Ho Help
 

I'LL TRY THAT,

Re: 496 Mag Ho Help
 

I had a faulty exhuast manifold temp sender, check the temps, will running and see if one is high. Mine would read 200 deg, before i even ran the boat.

Re: 496 Mag Ho Help
 

ok lets do this right,
waterpressure at idle should be about 5 psi, at 3000 rpms it sould be about 14-20 the 496 will read manifold temps find out what your exact seawater psi is all the falts that you mentioned are for things that are not hooked up so you will alwats have those faults. you need to run the boat and see what the data is as it goes into gaurdian and i would say that what it is is not a hard fault....but fault seconds should show what it was go to fault seconds and pull up gaurdian and it will showw what the reading where at that point!!!!!

Re: 496 Mag Ho Help
 

The guardian time is cumulative, and if it has never been erased, the time keeps climbing every time the buzzer goes off, regardless of what sets it off. as suggested, clear the history, and try again. Having the scan tool connected while running is also a good idea.

Re: 496 Mag Ho Help
 

Ok, some more questions. What year is your boat? Do you run it in salt water? Did you have an alarm before you did the pump and is that why you did it?

John :D

Re: 496 Mag Ho Help
 

Fixed, it was the Sea water pump water pressure switch. I replaced it and ran with the DDT, no codes
Thanks for the help.